AOpen Debuts The Funniest Motherboard Ever

Anonymous Coward X-11 writes "Has AOpen gone flipping nuts by putting vacuum tubes on its motherboards? AX4B-533Tube No, it's not replacing logic ICs with discrete components. The tubes are part of the on board audio. Not sure if they are serious about this. April 1 was two months ago." As an owner of a tube headphone amplifier I applaud AOpen's move to accomodate the high-end audio enthusiast, while simultaneous wondering about the ability of a switched psu to properly drive a tube amplification stage cleanly. There's no way this is for real, right? Right? Here's a link that seems to work pretty well. And this looks pretty, well, real. Update: /. reader Jedi1USA noted that HardOCP has more pics of the board.

Comments

Oh that's what I need...

[spoco2]

More heat in my PC Box... that's a top idea. In fact, along with a couple of valves, let's throw in a few radiator elements, then you could have a PC case that you can cook mashmallows on.... mmmm, sweet, sticky goodness.

Re:Oh that's what I need...

[squarefish]

it's only a matter of time before some mod bastard figures out how to water cool the tube!

Re:Oh that's what I need...

[j1mmy]

sweet sticky goodness? my pc gets plenty of that, what with all the porn ...

Re:Oh that's what I need...

[ecarlson]

If you water cooled the tube, it would stop working. The tube contains a heating element that heats it up so it will function.

Re:Oh that's what I need...

[Phork]

umm, there are water cooled tubes, uasualy they occur in RF amps, some older FmM broadcast stations used water cooled tubes in their finals. Water cooling a tube will let it work at a higher current than it is rated for. Basically the water cooling is to keep it from getting any hotter than it is supposed to get. The water cooling doesnt take it down to 50 deg F, it keeps it at the ideal operating temperature.

Re:Oh that's what I need...

[HerringFlavoredFowl]

Water Cooled Tubes are in many high power modern RF transmitters ... I have yet to see a solid state high power AM transmitter. Semiconductors can just not take the power load.

Water cooled tubes are designed and built to be water cooled. When I did college radio we had an Old Harris transmitter that use to melt the tubes on us (as in the tube would come out as a glob of glass). We replaced it with a prototype first generation Harris Solid State FM transmitter ... and was in 1995.

Check out Harris for more information on high end RF systems. Hmmm... looks like they do have solid state high power AM transmitters now ... amazing

Re:Oh that's what I need...

[jovlinger]

s/radiation/convection/

and i'd agree with you.

Re:Oh that's what I need...

[WNight]

Probably not, if you started cooling it before turning it on.

The cracking of glass comes when part of it is hotter than the rest and the uneven expansion causes stress.

Glass that can take quick heating and freezing isn't as tough as it is low-expansion over the normal heat range.

However, water cooling a tube would probably be mostly useless. You'd be cooling the glass, the part that rarely suffers heat-related damage, and pumping more power to the inards, the stuff protected from losing heat to the glass by a nice vacuum.

My dad says...

[ColGraff]

My dad claims that some people like the sound of vacuum tube amps, so maybe this isn't nuts. But how do they deal with unfortunate tendency of vacuum tubes to burn out?

Re:My dad says...

[pryan]

It's common knowledge with audiophiles and professional musicians that vacuum tubes are better than solid state technologies at reproducing sound. The highest quality amplifiers in the world use tubes. Most classical concert halls use tube amplifiers.

Re:My dad says...

[Russ Steffen]

Yeah, but tubes don't automatically mean better sound. Junk is junk with tubes or without. There are plenty of tube amps that sound like crap.

Re:My dad says...

[RadioheadKid]

Most classical concert halls use tube amplifiers.

As someone who has worked in the sound re-inforcement business, yes tube amps sound great, audio-philes love them, but well designed transitor amps can sound great too, and are much more practical, power efficent, smaller and cooler (temperature) I'd like to see some evidence to back up your vague statement.

Re:My dad says...

[ShinGouki]

same way you deal with tubes in amps when they burn out. simple 3-step process:

1) buy new tube
2) remove old tube
3) insert new tube

entire operation takes about 30 minutes (assuming you live 10 minutes from a music store with tubes ;P)

i've got an ampeg bass head (1200 watts (!)) that i can re-tube completely in about 10 minutes total...not really that hard an operation :)

Re:My dad says...

[Andrewkov]

I'd like to see some evidence to back up your vague statement

This isn't evidence, per say, but as a semi-serious guitar player I can tell you that solid state guitar amps tend to sound harsh and sterile, while tube amps have a warmer sound to them. Modern effects processing can simulate tube amps quite well, though. I've never heard of anybody prefering a tube amp in their home stereo.

Re:My dad says...

[norton_I]

Well, there is a difference between a guitar amp and a stereo amp. For a guitar, the amp is really part of the instrument. Tube amps definately do mess with the sound, but the player desires that to get the sound they want.

For stereo use, the goal of the amp is (or should be) to reproduce with the highest fidelity possible the sound as recorded. There, while tube amps tend to be better than "cheap" solid state amps, a high end SS amp is at least as good as a high end tube amp.

I do know people, however, who prefer tubes on their stereo for whatever reason (mostly snobbery, IMHO). A lot of audiophile companies make ones with tube pre-amps and a SS final stage and/or all tubes. I haven't found these systems to sound particularly better than some high end SS amps.

Re:My dad says...

[gad_zuki!]

Almost every guitar amp you've ever heard is tube powered. All serious (or non-broke) guitarists use tube amps because of the warm natural distortion of tubes and the ability to punch up the gain to get a very distinct distorted crunch. Solid state sounds flat compared to the tube.

In audiophile circles its pretty much the same deal, you can get a nice warm but low-keyed 'distortion' out of an amp that many audiophiles prefer to solid state.

Re:My dad says...

[phliar]

And my dad says tubes suck, smoke signals made by an authentic wool blanket and damp mesquite is the only way to go. I bet my dad can beat up your dad.

Most classical concert halls use tube amplifiers.

Classical concert halls use no amplification -- what you kids would call "unplugged." (I am a musician. I also have season tickets to the San Francisco Symphony.)

You can design a solid-state amplifier that has exactly the same distortion and non-linearities of tube amps (but why?) -- that's not good enough for golden-ear audiophiles though. They'd rather listen to their "Test LP" on their custom turntables and talk about sound-stage separation and the "special warmth" added by the special green CD markers and about how analog is obviously better than digital because what if the signal changes between those digital samples? Me, I'd prefer no distorion, and in any case I'd rather spend my time and money on music, not equipment.

(There are a couple of reasons to use tubes, where solid state devices don't work very well: very high power applications, like broadcast radio and TV transmitters' final stage RF amplifiers; and microwave tubes, like klystrons and magnetrons.)

Re:My dad says...

[Zeinfeld]

The highest quality amplifiers in the world use tubes. Most classical concert halls use tube amplifiers.

They may in the US. The classical concert halls I am familiar with use live performers without amplification of any kind...

Re:My dad says...

[zerocool^]

And it should be noted that this won't improve the sound quality of your 112Kbps MP3's.

Also, i want to know about digital capabilities. Does the board have a breakout box, or optical out / in? Plus when you plug a minijack into the back, you're getting a low level out (passive), and it gets sent to your Klipsch pro medias to be amplified, which are decidedly solid state. Isn't that going to degrade the sound.

Don't get me wrong, i WANT this board, but i need to know more about it first, and the first link is down.

~Will

Re:My dad says...

[ninewands]

Quoth the poster:

It's common knowledge with audiophiles and professional musicians that vacuum tubes are better than solid state technologies at reproducing sound.

It's common knowledge (among audio engineers, because MOST "audiophiles and professional musicians" don't understand the electronics involved) that a vacuum tube power amplifier operated in a push-pull configuration and biased for Class A operation produces less distortion than the designs commonly used for solid-state power amps. HOWEVER, a solid-state PA operating under the same conditions will produce just as clean an output and waste just as much power and generate as much, if not MORE heat.

That being said, I read the tech specs on the board and find it a woefully inadequate attempt to cash in on the "coolness factor" alleged to apply to tube amps for audio.

The tube on the mobo is a dual triode. Since it's being fronted by a stereo sound circuit, push-pull design is out of the question. It's just a straight-up dual-channel, single-ended power amplifier. This coupled with the fact that (IIRC) most multi-section tubes are directly-heated (the filament IS the cathode instead of just a heat source), indicate that improvement in perceived audio quality will be minimal at best.

Without seeing the schematic for the amp, I can't give an opinion about it's stability, but triodes tend to be fairly susceptible to parasitic oscillations if they are operated at more than moderate power gain without HEAVY bypassing. This hefty use of capacitive filtering is what gives tube amps their reputation for "warmer sound". The fact is that a lot of the higher frequencies are bled off by the bypass capacitors.

Class A amps typically have a plate efficiency of 35 percent or less. This, coupled with the existence of the tube's filament (heater, for the Brits among us) indicate that the tube is going to produce PRODIGIOUS amounts of heat for a minimal improvement (if any) in true audio quality.

In short, I see it as a "gimmick" mobo.

Re:My dad says...

[sigwinch]

All serious (or non-broke) guitarists use tube amps because of the warm natural distortion of tubes and the ability to punch up the gain to get a very distinct distorted crunch. Solid state sounds flat compared to the tube.

True, but I wonder why they don't digitize the signal, apply any distortion curve they want, then convert back to analog. All the benefits of transistors, but you can dial in any distortion and other effects you can imagine.

Re:My dad says...

[Eil]

It's common knowledge with audiophiles and professional musicians that vacuum tubes are better than solid state technologies at reproducing sound.

But it's not-so-common knowledge that solid state technologies can reproduce the exact same sound as tube amps. In fact, digital equipment can reproduce any sound with any quality distinguishable to human ears.

Then why do we still keep hearing people remark about how tube amps are just "better" without offering any further explanation? The answer: tube amps add a defining "warm" quality to the sound, whereas solid state circuitry reproduces it quite a lot more accurately (but not always perfectly depending on your equipment, same goes for tube amps, actually) than tube amps. That is, without the "warm" quality.

It's not about quality or which is better, it's about the characteristics that get added to the sound due to the type of components in the circuitry.

I'm not bashing those who like tube amps, just pointing out that solid state and digital are not inferior, just more accurate. A lot of people don't want accurate sound, they want nice sound. I can't say I disagree with them, honestly.

Re:My dad says...

[Woek]

Genuinely curious: what's not solid state about a tube amplifier?

Re:My dad says...

[lucius]

The cathode rays.

Re:My dad says...

[TaliesinWI]

I completely agree about the "gimmick" mobo moniker. This tube is going to provide a warm glow to the inside of the case more than it's going to affect the sound.
I also can't imagine what kind of microphonics (surrounding vibration being transmitted thru the tube and ending up as noise) you'd have here.

And although it's gratifying to see people pointing out the difference in what the tubes are "for" in a tube guitar amp and a home audio amp, there are the people coming out on the whole "pleasant distortion" thing, but then dropping it in the dust without really explaining what they mean.

So, here goes (I'm grossly simplifying to try and keep this brief):

Simply put, tubes add more distortion than transistors. However, tubes add most of their distortion in the even harmonics of a tone, whereas transistors add distortion in the odd harmonics of a tone. Why does this matter? Because the way we humans tell various instruments apart is in the amount of harmonics that the instrument produces for a particular fundamental (this is called timbre). This is why even though a flute and a guitar are both playing A440, they sound radically different. Naturally occuring musical harmonics are "even", that is, even multiples of the fundamental frequency.
So, when a tube amp reproduces the sound of a saxophone, it _is_ distorting the signal by amplifying, for example, the second, fourth, and sixth harmonics. Our brain takes these "natural" harmonics and internally boosts the level of the fundamental tone - in other words, we are psychologically reconstructing the musical note as slightly "louder" than it actually is.
In comparison, the transistor amps, while producing far less total harmonic distortion (the vaunted THD that we see in so many specs), are actually producing more "unnatural" distortion, because they are affecting the odd harmonics of a given tone, even slightly. Since these harmonics are not "naturally occuring", our ear-brain doesn't compensate for them in the same terms, so it registers as... well, kind of odd. More grain on the sound of a string. Harshness in wind instruments, etc.
In some ways, the tube/transistor battle is "pick your poison", kind of like the whole digital/analog debate. Some people argue that music should be reproduced with as little distortion as possible, so transistor/digital is the way to go. Other take the position that distortion-free sound reproduction is impossible, so if you're going to have it, might as well make it the kind that is more "natural" - tube/analog.
(Yes, I know I've trivialized lots of the debate - I'm not going to re-fight the audiophile wars here.)
In the end, it's what Sounds Better to You.

And for what it's worth, I own both tube and transistor equipment, and own a CD player and a turntable.

Re:My dad says...

[mindstrm]

But he was right. He stated that it's common knowledge among audiophiles that tube amps are superior.
Just like they know that vinyl is superior to anything digital.

That I'll agree with. Not that they are right.. but they definately think so.

Re:My dad says...

[ninewands]

how can a push-pull amp be biased for Class A? Both drivers in the totem-pole would be on continuously.

That's true, the definition of Class A operation is that the stage passes current at all times. The 2 active devices of a push-pull amp operate 180 degrees out of phase to each other, but if the power supply is properly designed and regulated, they don't feel each other anywhere but at the output.

BTW, most "audiophile amps" that use a push-pull output stage tend to be biased for Class B operation (each device conducts for exactly 180 degrees of the cycle. This operation induces switching transients into the signal when the devices switch off and on at the zero crossing, but they are minor and rarely audible, and Class B operation is MUCH more efficient in terms of power out vs. power drawn from the supply.

Re:My dad says...

[JabberWokky]

But it's not-so-common knowledge that solid state technologies can reproduce the exact same sound as tube amps. In fact, digital equipment can reproduce any sound with any quality distinguishable to human ears.

I'm on the whole "solid state is good for music" wavelength with you, but guitar amps are kinda a special case - they are designed to be driven past the "normal" limits, and it's that breakdown in fidelity that a tube provides (and which is unique to each variant of tube) that you're after. Sure you can model the whole thing, but at a certain point, getting the sound right when you're laying down a strong bass with harsh pops with your thumb while going up and down the high treble hammering and sliding... well, it really just is easier to use an "analog" devide like a tube. It's the subilty of the extremes that tubes get right - or rather, they get it wrong, and that's what's wanted. And to 99.9% of people who listen to the music, it makes no difference whatso*ever*. But, when you're performing, you can hear the difference between your fingernails at one length and 1/16th of an inch longer, and for a musician, it's all about the tiny little details. Hell, I play almost entirely acoustic nowadays, and I like listening to the sound slowly alter in the morning in the woods as the humidity changes as the sun burns off the fog and dew. Does that mean that I care? Hell no... I just *notice* - that's what musicians do when they play. Each musician cares about different things... some *really* care about their amp sound. More power to them.

You can hear all sorts of things in high fidelity headphones while listening to Zeppelin or the Beatles - talking off to the side, older demo tracks, etc. They were never *intended* to be played on high quality speakers with a recording as good as the master. (And if you're listening _solely_ for those little things, you're doing what someone up above pointed out - audiophiles listen to noise, not music) Kinda like how SciFi props for TV shows look like painted crap in real life - they are intended to be shown on a really fuzzy NTSC or PAL screen. Fidelity is great to a point - movie soundtracks are much more clean than most albums simply because they *know* they are going to be played in a digital theater, whereas albums are (usually) meant to be enjoyed for the music.

Let the musicians be anal about the sound - it's your job to get laid with the music going on in the background, or blare it while driving down main street with your buddies singing along, or sob into your beer about how that guy on the jukebox is singing about how she left you, or otherwise just make part of your life. I've spent my time in darkness in a comfy chair, eyes closed, listening to good headphones... the goal is still the same: Enjoy your music.

--
Evan "First got laid to Grateful Dead, was listening to the Brandenburgs when I found out about 9-11, listening to Crowded House, Kill Eye right now".

Re:w00t

[TheProteus]

I bet you've got a 12AX7 on there, considering they said it had a 'dual triode' tube in there. They're also some of the cheapest valves out there.

who are they kidding?

[hifizen]

As an audiophile and electrical engineer, I can tell you that no serious music (tech) lover will take this seriously. It's common knowledge amongst audiophiles that high quality audio can only be reproduced outside the electrically noisy environment inside a PC case. But more than that, audiophiles are a particular, fussy lot, and they all have their own preferences for this tube type or that.

Who are you kidding, AOpen? Leave the high-end audio to the specialists, and leave it off your mobo!

Websurfing done right! StumbleUpon

Re:who are they kidding?

[User 956]

I can tell you that no serious music (tech) lover will take this seriously.

Most musicians are not engineers, and vice/versa. (I happen to be both, so I'll be glad to translate). Musicians are interested in sound production, and everyone else in sound REproduction. These are two totally unrelated things. A guitar amp is SUPPOSED to add distortion and tonal coloration to the signal. In fact tests for frequency response and distortion as applied to Hi-Fidelity equipment mean nothing when done on a guitar amplifier. We WANT to modify the original sound. That's exactly what the designers at Martin were doing from day 1. An acoustic guitar has a resonating chamber, a sound hole, and a front and back surface that act as diaphragms. If we could plot the frequency response of a single string played back on a good acoustic guitar, we would see all kinds of nastiness. Violins... the same thing. Saxophones... ditto. Pianos... of course. The sound quality of an instrument, what we call timbre (pronounced tam'ber) is a highly desired characteristic. It's what separates the Steinways from the Wulitzer uprights and the Martins from the Hondos, you get the idea.

In an electric instrument, there are no resonating chambers to add flavor, so we add it with distortion instead. Distortion, the crux of the biscuit..... sometimes we want it, other times we don't. That's what always bugs engineers and audiophiles alike. When you're trying to REproduce an already distorted sound, you don't want to add any additional distortion from the amplifiers. And you certainly don't want to add transistor distortion products. Sometimes tube distortion on a clean signal is OK. What, did I just contradict myself? No way, Jose'.

Here's the point of this whole exercise:

TUBE AMPLIFIERS SOUND DIFFERENT FROM TRANSISTOR AMPLIFIERS PRIMARILY WHEN THEY DISTORT!

You can see it on a o'scope, hear it with your ears, and prove it on paper, so I know it's true. And here's why: Transistors and tubes use different principles of physics for operation. Valve amps (the original name for tube amplifiers) are basically voltage driven, so when they distort, even-order harmonics are produced (2nd, 4th, 6th, etc...) while transistor amps are current driven and produce odd-order harmonics (3rd, 5th, 7th, etc....) When you look at them both on an oscilloscope, the transistor amp flattens out the waveform, while the tube amp sort of makes a triangle wave. If we look at the inherent resonances of acoustic instruments we find that things like violins make lots of even order harmonics, while things like clarinets make lots of odd order harmonics.

Now, do we want our guitar to sound more like a violin, or a clarinet? Ah yes, the violin is much more "sweet" sounding. That's because the human brain likes and will tolerate much more even-order distortion than it will odd-order. One of the great distortion boxes in recent history is the Aphex Aural Exciter. The guys who designed this thing were marketing geniuses. The original units were sealed boxes with tamper proof hardware. They were leased to studios for final mix down. Once a few big artists like Linda Rondstat and Fleetwood Mac used and liked them, their place in audio gadgetry was assured. Of course they just use a clever method of picking out the fundamental note of say a human voice, making a little distortion, and adding it back to the original signal. This adds "warmth" or "depth" to the sound that can be, well, exciting. Our theory about odd vs. even distortion holds up because while the first units made lots of odd harmonics, several years later I remember an engineering release that hyped a new distortion circuit with increased the 2nd order distortions, while reducing the 3rd order products. Sound's very interesting doesn't it? They made a way to produce "tube" sound in a device that's basically used on vocals and strings. Again, the brain likes even-order distortion while finding odd-order somewhat irritating.

There's some tricks to be used for making distortion. You can get transistors that are voltage driven called MOSFETS. In my opinion, they can be made to sound like tubes if properly designed. Also, once a signal is digitized, it can be made to sound like anything in theory, if the proper algorithm is applied. The problem is, they've been working on the sound of a Strat going through a Marshall for a long time. It's hard to beat the sound of a well designed tube amp, but they're beginning to learn how. Some of the new Multi-EFX boxes like the Quadraverb do an amazing job at processing a guitar. But I've found that they still need to go through a speaker to smooth out the sound. (There's additional distortion, coloration and bandwidth limiting produced by all loudspeakers)

Now for all you guys and gals who like their transistor amps and fuzz boxes, there's nothing wrong with what you do. Sometimes odd-harmonics are needed to cut through the mix. I sometimes purposefully loop a guitar track back into an overdriven channel on my board just to "dirty" it up a little. It can make a bland lead really stand out at times. But it's just a matter of taste. I really like the even-order distorted, bandwidth limited, compressed sound of a traditional tube amp for guitar.

But REproduction is a different story. I've got preamps that are rated in parts-per-million distortion. I tweak all my tape decks for the flattest response possible, and work hard to get the best signal-to-noise ratio possible. That's because I like the final sound to be as faithful to the original as possible.

Re:who are they kidding?

[Jucius Maximus]

"As an audiophile and electrical engineer, I can tell you that no serious music (tech) lover will take this seriously. It's common knowledge amongst audiophiles that high quality audio can only be reproduced outside the electrically noisy environment inside a PC case."

True, and PCs themselves are acoustically noisy as well. What's the point of super high fidelity sound reproduction when you've got hard drives, dvdroms and fans whirring in the background?

Re:who are they kidding?

[Monkelectric]

that was my reaction :) I have some tube-amps in my guitar rig and I can't get them *NEAR* my computer because they pickup the volumes of EM noise that are currently makeing me sterile :)

Re:who are they kidding?

[Shelled]

Don't look at it as a stab at high end audio, but as a classic example of the wonderful lunacy of the Far East audiophilia. This is after all the region where audiophiles first went nuts over the sound of 1930's film-house Western Electric tube amplifiers, some powerhouses at 10 watts, spawning hundreds of lower power (!) iterations costing thousands per channel.

Re:who are they kidding?

[optikSmoke]

I can tell you that no serious music (tech) lover will take this seriously.

Though I am not too knowledgeable in the particulars of audio/music tech, I gather from your comments and others that this board is not geared towards people who actually know anything about sound, but rather those overabundant people who believe to their core they know everything about it, and don't..... I happen to know one or two. Blaargggh

Re:who are they kidding?

[PurpleFloyd]

Edison, however, discovered that a heated filament emmited electrons. In fact, this phenomenon (at the heart of all vaccum tube technology) is called the "Edison effect". AFAIK, it was his only discovery in pure science.

Re:who are they kidding?

[Chasing Amy]

> high quality audio can only be reproduced outside the electrically noisy environment inside a PC case

Not strictly true--just use adequate RF sheilding. I use my PC for everything, including sound that would even be pleasing to audiophiles who didn't know where it was coming from. I use a modified high-end soundcard sheilded all around down to the sides of the PCI slot, and I've made a DIY Corda-type headphone amp (thanks, Head-Fi.org and Headwize.com!)inside a sheilded drive-bay box. Nothing is truly "external" to the PC, though it may as well be because the effect of the sheilding is the same.

RF sheilding and Faraday cages, people! It *can* be done, with a lot of elbow grease.

Re:who are they kidding?

[plastik55]

What have you done about your power supply? The switching supplies usually found in PCs can produce a lot of noise which will find its way to the sound card no matter how well it's shielded.

Re:who are they kidding?

[Ogerman]

Analog distortion does wonders for digitily degraded sound, it adds harmonics and generaly livens up the sound, removing that "flatness" that is otherwise quite hard to get rid of.

You can do the same thing with DSP. Try the "Crystality" plugin for xmms. A little Freeverb might also help if it's a terribly flat recording. There are also some LADSPA plugins that might be useful.. tube sims, harmonics processors, etc.

Re:who are they kidding?

[evilpenguin]

The guy's long post above is dead on. Yes, MOSFETs are transistors (Metal Oxide Semiconductor Field Effect Transistors, in fact: MOSFETs), but the point is that MOSFETs, like vacuum tubes are voltage amplification devices, while all other transistors are current amplification devices. This has huge consequences when the resulting signal goes through subsequent reactive loads (like the coils of the speakers, or the capacitors of filters).

None of this of course has anything directly to do with the original article, which simply must be a joke.

BTW, Even farther off-topic: know anyone who wants a professional tube tester? This thing is a classic, which changable modules of tube sockets, a scroll of tube types with test settings, vernier pots for setting the filiment and plate voltages, locking resettable push buttons that configure test signals, oscillators, reactances, etc. It belonged to my father, who was an electrical engineer for AT&T in the 60's and Control Data in the 70's and 80's. He had a commercial RT license (he did microwave transmitter maintenence for AT&T) and he was a ham. When I waqs kid he had a home business for Hi-fi and TV repair in his home. He had a complete electronics lab and parts shop down there. He died a few years ago and we're parting with the stuff we can stand to part with. The tub tester is way cool, but I have hardly any devices with tubes. Contact me if you are interested.

Re:who are they kidding?

[Golantig]

With regards to the violin emphasising even harmonics - it depends where the bow is playing on the string. If a string is bowed or plucked at an antinodal position, for a particular mode of vibration, then this mode will be accenuated e.g. bowing at the centre tends to accenuate the odd numbered modes (which relate to harmonics).

Re:who are they kidding?

[nolife]

It's common knowledge amongst audiophiles that high quality audio can only be reproduced outside the electrically noisy environment inside a PC case

Every time audio and computer are mentioned, you will always find a thread about computers making too much noise. Self proclaimed audiophiles will bitch about everything. I suggest that you try to make some music on the PC before jumping on the noisy bandwagon. I have made several hundred elctronica type audio files on my PC's over the years. I start with a midi file, record to wav and burn them as audio cd's. That's kind of the simple version, I do not make the original midi files but I usually spend 10 to 20 hours on a song tweaking the instuments, channel reverb, chorus and volumes etc... The only limiting quality factor is the initial instrument quality that you sound card has. Some of the best files I have were made with a generic $14 Yamaha chipset hardware wavetable card in combination with an old Soundscape Elite. The SB live is good also but I do not like the stock instrument definitions that come with the card.

My home stereo consists of a recent Yahmaha reciever and a Yamaha M4 amp (old but good) for the subs. Driving roughly 10 year old Infinity's. The sound quality of my files is better then 99% of the cd's I have bought in the store and rival some of the DDD Telarc labeled discs like BachBusters and Beethoven Or Bustfor background noise, hiss, and dynamic range.

Re:who are they kidding?

[haggar]

And here's why: Transistors and tubes use different principles of physics for operation. Valve amps (the original name for tube amplifiers) are basically voltage driven, so when they distort, even-order harmonics are produced (2nd, 4th, 6th, etc...) while transistor amps are current driven and produce odd-order harmonics (3rd, 5th, 7th, etc....)
The fact that tranjo's are current driven while tubes are voltage driven is NOT the reason for the difference in distortion! The reason for it is, simply, in the difference of the transmission curve. The rest of what you said is OK, but it has no bearing whatsoever with the driving method of the device.

Re:who are they kidding?

[Dirtside]

That's because I like the final sound to be as faithful to the original as possible.

Maybe this is a silly question (about half of what you wrote is gibberish to me), but without actually having been in the studio and having heard the original recording, how do you know when your reproduction of a recording is faithful to the original? I mean, obviously we can assume that if you hear an A-flat on the record, the guitarist played an A-flat in the studio, but when it comes to subtle harmonics and exact timbre and whatnot, how do you know that you've got it right?

Re:who are they kidding?

[Chasing Amy]

> The switching supplies usually found in PCs can produce a lot of noise which will find its way to the sound
> card no matter how well it's shielded.

First, better-quality power supplies are usually made of better components, and better sheilded from the start, producing a less dirty EM noise. I like Sparkle power supplies myself, though many others are as good or better.

Second, I don't see the power supply as a big issue since my soundcard and headphone amp are sheilded--the soundcard with a little steel RF sheilding cut to fit around it and given a couple layers of nonconducting paint just in case it accidentally touches something, as well as a rubber "footer" at the bottom so that it can rest flush with the motherboard around the PCI slot. There's one hole (covered with mesh, anyway) in the RF sheilding on the side away from the power supply, with a duct leading to a fan mounted on the back of the case for venting so that the 24/96 soundcard can't overheat. The headphone amp is a Corda-type design built inside the drive-bay RF sheilding box from an old Creative 4224 CD burner that broke. The amp itself is in a small cardboard box wrapped in thin plastic, with a Faraday cage of metal mesh around that plastic, and another layer of thin plastic between the Faraday cage and the drive-bay box from the old broken CD burner. There's a hole in one part of the thin plastic layers (and through the cardboard, obviously) for an exhaust fan. It's fronted with a plastic drive-bay panel with holes for two headphone jacks (high-impedence and low-impedence) and the volume knob, and a vent hole for the small exhaust fan mounted on top of the front of the drive-bay panel. So, it's definitely better-sheilded from RF noise than almost any consumer amp.

Since I listen with a pair of nice Beyerdynamic headphones, noise from fans and drives isn't an issue.

The great thing is that anyone can do this on the cheap. Audiophile-quality headphones and headphone amps are very cheap compared to the money one would need to spend to get equivalent sound from speakers, especially since anyone with a willingness to learn to solder can build a great headphone amp for a very small price, and the plans are readily available from the two headphone sites I mentioned in my above post. The HRTFs in modern games and APIs even make headphones a good choice for gaming, too.

Re:who are they kidding?

[plastik55]

Your sound card is powered, no?

If your sound card is not powered then you can ignore your power supply as a source of noise. But if your sound card is powered, then it's got a direct electrical connection to your power supply through the PCI slot. The power lines lead directly out of the power supply and directly into your PCI connector.

Ain't no amount of shielding going to help you, if there's noise on the power supply. Switching-mode supplies produce a godawful lot of noise.

Before everyone goes crazy...

[saihung]

making fun of this, please keep in mind that some of the best high-end amplifiers made today still use vaccuum tubes. Tubes are capable of making extremely high-quality sound, and whether this is because of their "warm sound" as enthusiasts claim or just because of sound degradation that sounds good to some people - well, that's just a matter of personal preference.

That there are any options for high-quality on-board audio at all - this can only be a good thing.

gonna wait

[Anonymous Coward]

A move in the right direction. I think I'm gonna wait for the version with a tesla coil on it tho.

This is like....

[ColGraff]

Buying a new car that has automatic transmission, 60mpg, dashboard computer, GPS, and also an 8-track player. And by the way, vacuum tubes and AGP slots were never meant to be in the same picture. I'm sorry, but it just ain't right.

Re:This is like....

[edrugtrader]

no... to an audiophile this is like getting automatic transmission, 60mpg, dashboard computer, GPS, and a live band in your dash.

Re:This is like....

[Indras]

Dude, don't diss the 8-track players. My first car had one, the best damned anti-theft device I've ever seen. If you really don't want your car stolen, buy an old 8-track player and put it in, then throw some 8-tracks around on your passenger seat.

You could leave the thing unlocked with all four windows rolled down in a dark alleyway in Chicago, and nobody would touch it.

What kind of tubes?

[cporter]

The important question is, what kind of tube is it? There's only one, judging by the picture. Is it an output tube? Another question: cooling. Tubes get damn hot.

A lot of audiophile tubes are sourced from Russian or Chinese factories. It would suck to blow the tube playing GTA3 and have to wait 12 weeks for a shipment from the far east!

Re:What kind of tubes?

[AJWM]

From the pictures on harcop, it looks like a Russian-made Sovtek 6922 (aka E88CC aka 6DJ8). Here's the specs on a 6DJ8. Basically a dual triode like the 12AX7 but somewhat different characteristics.

audiophiles rejoice!

[Moosifer]

As a once snobbish, now reformed ex-audiophile, I cannot resist but slip back to the affected, bombastic days of my youth and exclaim "It's about freakin' time! Now when are we going to replace these markedly inferior CD-ROMs and DVD-ROMs with the gloriously mellifluous LP-ROM?"

Re:audiophiles rejoice!

[DaedalusLogic]

Dude, I was thinking the exact same thing! Check out my post. Now will it be USB 2.0 or 1394 connected...

DL

Re:audiophiles rejoice!

[GoRK]

Fuck LP-ROM. Let's replace DVD-Video with Vinyl Video!

Re:audiophiles rejoice!

[hawk]

yes, they were much more interesting then, and you could build something from scratch that would keep up with anything commercial. And clever design still counted for a lot . . .

Anyway, it goes back farther than that. Somewhere in my stuff is an entire LP full of morse code at various speeds for learing it . . . something I never got around to doing, and don't have time for now . . .

hawk

Don't see how it's possible....

[lucifuge31337]

There aren't enough components on the board (that I can see) unless there is an external power supply.

Most tubes are going to require abot 16,000 volts to the grid. You'll need a nice-sized transformer to step up normal line current to that. And if it's powered off the MB power harness.....well, I son't think that's even possible. What's the highest voltage there? 12v? That trnasformer would have to be huge.

And all of that isn't even taking in to account the heat problems.

Re:Don't see how it's possible....

[jhines]

No, that is for a CRT, standard audio tubes work on a few hundred volts.

And it is the plate of a tube that gets the B+ high voltage, the grid regulates the current flow, and uses a modest voltage.

A tube amplfier has 3 power supples:
A- to power the filaments (6 or 12v AC)
B- Hi voltage DC, in the 300 volt range
C- Low voltage DC, to power the grid circuits

Re:Don't see how it's possible....

[hifizen]

"Most tubes are going to require abot 16,000 volts to the grid."

um... try 160V, at about 5-10mA for your typical preamp tube. Then about 6 or 12V for the filament. Piece of cake for a switched power supply...

The small tubes will contribute some heat, but we're not talking power output tubes, so the extra heat generation should be minimal - well within a PCs cooling limits.

Websurfing done right! StumbleUpon

Re:Don't see how it's possible....

[xercist]

What's the highest voltage there? 12v?

Actually ATX supplies both +12 and -12, so the highest voltage is 24V. Not saying it would make a difference, but...

Re:Don't see how it's possible....

[Dr Caleb]

From the article:

By incorporating a switching mode power supply for the tube circuitry that can truly rival solid-state amplifiers, then employing A Maxim 668 DC-DC voltage converter to provide ample voltage for the tube to function under optimal conditions

....with minimum 50,000 MTBF hours on the motherboard, and 35,000 MTBF hours on the tube circuitry (Tube itself will have about 4,000 to 5,000 hours, depends on operating conditions...

If I got only 5000 hours of driving in my car before it went *(poof)*, I wouldn't buy it. I don't care if they gave me a traditional Geshia for 5000 hours, the MoBo isn't worth it.

Re:Don't see how it's possible....

[darkwiz]

You apparently aren't an EE. There are a number of ways to do voltage multiplication without a (large) transformer (technically, you can do it without the XMFR, it just helps).

Here is one way. I'm too lazy to try to find a better link with some theory attached, but if you follow the current path on the voltage swings, you should be able to figure it out.

Re:Don't see how it's possible....

[Shelled]

Not necessary. Tubes will run at relatively low voltages. The entire early history of radio was powered by low voltage batteries. It's why the power supply voltage came to be know as B+. Decades of car radios ran on tubes.

Re:Don't see how it's possible....

[John Miles]

16,000 volts? On the grid? Score:5, Informative?

Kill me now.

Re:Don't see how it's possible....

[1010011010]

If I got only 5000 hours of driving in my car before it went *(poof)* ...

...then I would say you probably bought a car made by Verizon...

Re:Don't see how it's possible....

[norton_I]

I assume you don't buy lightbulbs, then? And it is shameful that you have to refill your gas tank every few hundred miles.

I am pretty sure this is a joke some engineer at AOpen wanted to have at the expense of the particularly dumb crop of audiophile wannabes who think they can be leet by having a tube amp hooked up to their AC97 audio codec.

But tubes burn out, and have to be replaced.

Re:Don't see how it's possible....

[ortholattice]

Most tubes are going to require abot 16,000 volts to the grid. You'll need a nice-sized transformer to step up normal line current to that.

I think others have already mentioned that most tubes require 100-300 volts on B+ for the plate. And -3v or so is typical for a control grid (although B+ is usually applied to the screen grid, which does not control the signal but has a different purpose). In the 1950's car radios had tubes that used 12 volts for B+.

BTW the only power source mentioned on the data sheet is a 3v lithium battery. (I am tempted to joke that they neglected to mention that it was the size of a refrigerator and required 2-inch copper bus bars. Oops, I just did. Yeah, I know it's for the CMOS clock chip.)

Re:Don't see how it's possible....

[ninewands]

The "B" for the plate voltage supply was the source of the name of the B "cell" battery, which produced 120 vdc. Sorry, in my book that's NOT low voltage because I've taken some pretty nasty shocks from a 12 volt battery in a car on a hot (sweaty) day.

Having read some of the other posts in this topic, I think this is a joke by the engineers at Aopen. I saw a reference to a 300 volt plate voltage in the writeup on their website. That sounds kind of high for a dual-section triode in a "miniature" envelope. 120-150 volts would be more reasonable, but it's STILL more voltage than I'd want on the same board as a $200 (or more) 1 GHz microprocessor.

Re:Don't see how it's possible....

[HerringFlavoredFowl]

These days you can fit the necessary DC to DC stepup converter inside a package the size of a match box.

Hamamatsu makes several Photo Multiplier and Photon Counting Tubes that run off of 5v and internally generate up to 1500 volts. The voltage is clean enough to run a photo counter. The step up converter is small enough to be hidden in the tubes socket... That's what Hamamatsu does.

Re:Don't see how it's possible....

[Dr Caleb]

Yes. Compact Flourescent. 50,000 hours lifetime. I do have to fill the tank, but I don't have to replace the motor every few hundred miles ethier.

looks like a hoax...

[djtack]

Neat photo, but a couple of problems:

Chrisd's right on about the power supply, valves have pretty demanding power requirements, and the voltage is much higher (300+ volts is typical) than what's normally present in a PC.

Also, most tube amps require output transformers, which is noticably absent from the photo.

Thirdly, there's only one tube! Presumably, if they are really after the audiophile market, it would at least be a stereo amplifier. Not to say anything about the noise problems present near high speed digital circuits. This is bunk.

More interesting reading...

[Incongruity]

ArsTechnica ran a bit about this recently and they have some interesting discussion over there as well.

You can also check out a IEEE story they link to about vacuum tubes and their uses in modern audio.

New disk drive also in development for this board.

[DaedalusLogic]

It uses physical forms actually cut into a vinyl disk to reproduce sound. Rather than a traditional 5 1/4 disk bay it will be a USB 2.0 periperal and look something like these devices. Analog audiophiles rejoice! I play guitar and I do have to say I enjoy the sound of a classic tube amp. I wonder how odd and expensive will it be to say... Uh yeah I need a vacuum tube replacement for my computer.

Still, could be interesting for your HTPC

Umm.... looks like a wannabe IT7 or AT7?

[Hollinger]

Does this look like a johnny-come-lately AT7 or IT7? While the Abit offering looks like a smash hit (according to some review sites that I refuse to promote), this looks like it's a niche market at best. How many of these do they hope to sell? I understand that there are people who've spent more than the price of a cheap BMW on their stereos, but why, oh why, would they buy this for their computer? Can you get a DAT player for computers these days?

Re:Ahhh...

[edrugtrader]

[Timeout expired]

uh... so it the odbc connection timed out, or the time it allows to timeout expired?

i think [ODBC fuckup] explains it much better.

What exactly will this tube be doing?

[handsomepete]

I'm honestly asking. Would a single tube of that size after digital processing really have a major effect on sound quality? I thought the neat thing about tubes were the warmth and natural distortion they provide (in the same way as analog recording). If it has already gone through digital processing with the inherently less forgiving limits and peaks, wouldn't that actually hurt the quality? And what's the deal with that power input near the tube?

This whole thing seems kinda skimpy on details... I hope this doesn't give Creative any ideas. The last thing we need is a PCI SB Live card with this stuff on it:
This quality Creative Sound Blaster(tm) product requires the space of four PCI slots and a special attachment for your power supply.

Re:What exactly will this tube be doing?

[isaac]

And what's the deal with that power input near the tube?

That's no power input - it's the audio output header. See this HardOCP article (towards the bottom of the page) for a few more details.

I still think it's a gimmick, though. Really, the D/A should be external in its own shielded enclosure for optimum results.

Another gimmick of this board is that it includes a CD player application that you can boot into instead of Windows. Interesting, I guess.

-Isaac

Why your dad says that...

[fmaxwell]

Tubes tend to produce even-order harmonics when they distort. Transistors (except MOSFETS -- others?) produce odd-order harmonics. Of the two, odd-order harmonics are much more annoying from a psycho-acoustic standpoint and lead to what many describe as a "harsh" sound. Tubes also have the advantage of not clipping hard (producing a DC output) because they have to run through transformers to drive speakers and, as we all know, transformers don't pass DC.

That's a gross oversimplification that leaves out much that I know, some that I think I know but don't really, and stuff other people actually know that I don't know at all. But that's the gist of it.

Is it of any use on a motherboard? Sure. It's great gimmick to sell to idiots. So how do they get stereo out of a single tube? It looks too small to be the two-tubes-in-one variety.

Re:Why your dad says that...

[Shelled]

Dual tubes aren't rare, and they are usually small (proper term: receiving tubes, probably from the original use in radios.)

Re:Why your dad says that...

[Tiroth]

Two notes:

1) many line level tube circuits do not pass through trannies. There are many reasons tube circuits do not clip "hard", but the most common one is that tubes are low gain devices, operated with low (or no) negative feedback. It is NFB that "squares up" the clipping, producing the high order (nasty) harmonics.

2) I couldn't get to the site, but the most common tubes are dual triodes, which is quite sufficient for a stereo buffer.

Re:Why your dad says that...

[ncc74656]

Is it of any use on a motherboard? Sure. It's great gimmick to sell to idiots. So how do they get stereo out of a single tube? It looks too small to be the two-tubes-in-one variety.

It's probably a dual triode...a 12AX7 or something similar. 2 sections of 3 pins each (cathode, grid, plate) plus three for the heater (center-tapped so you can run it on 6V or 12V) makes 9 pins total, which was fairly common.

(I looked for clues that this might've been an April Fool's joke, but didn't see anything to say that was the case.)

Re:Why your dad says that...

[andyr]

So how do they get stereo out of a single tube? It looks too small to be the two-tubes-in-one variety.

It seems the tube is a Sovtek 6922 - which this page references as followed by one Sovtek 6922 double triode per channel.

Cheers, Andy!

Re:Why your dad says that...

[fmaxwell]

I stand corrected regarding the dual-triodes. It's been a long time since I dabbled with tubes and was thinking of power output tubes rather than line-level stuff.

The comment about not having a transformer is well-taken and was one of my reasons for being so critical. One of the selling points of "tube" sound is the soft clipping from the output transformer. On a transformerless design, you obviously lose those advantages.

Re:Why your dad says that...

[ncc74656]

I wonder if we can change out the stock tube (if it is a 12AX7) to maybe.. an old coke bottle sylvania or a squeeky clean russion SovTek tube :)

The pix at HardOCP include some closeups of the firebottle...turns out it's a Sovtek 6922, an industrial-grade equivalent of the 6DJ8 twin triode (the European equivalent is ECC88). Here's a page about the 6922 and friends from what sounds like an audiophoole perspective. (The historical info is interesting, though.)

For embedded market?

[Xunker]

One thing I noticed is that it has a watchdog timer -- that leads me to think they are posing it for the embedded market; specifically for those who want to integrate it as part of a high-end audio gear setup that requires minimal user interaction.

As an aside, don't tubes kick out a lot of heat? Any bets as to when we're going to see a Thermaltake Golden Orb for tubes? :)

Re:For embedded market?

[GoRK]

Dude, probably about 50% of all new desktop/server/etc. computers have a watchdog timer in them these days. Every new Intel chipset has one including the 845E that this motherboard uses. Some of VIA's chipsets have one. It's really hardly any work at all to put a watchdog into a chipset.

This board is about as useful to the embedded market as a 440hp straight-8 engine would be to a compact car manufacturer.

Crack Smokin'

[sfgoth]

Why do companies cater to these Audiophile nutcases? Stuff like monster cable, tube amps, and 20 lb power strips. What a waste of money...

Oh wait. Money. THAT's why companies cater to those nuts. I wonder how much extra this mobo will cost, and if they'll send out Jeves with while gloves and a new tube (for a sizable fee) when yours burns out.

-pmb

Well...

[cirby]

Compared to a high-end Pentium IV, a vacuum tube probably counts as a heat sink...

Does the board include a socket for...

[Snard]

... the Signetics 9046xN Write Only Memory? (which, as you recall, has V(pp) pins for the filaments)

Only one tube?

[ktakki]

I see only one tube and, considering the specs mention 5.1 surround sound, I can't see how this tube could be part of the pre-amp/power amp signal chain. I've owned a few tube amps in my time (stereo, guitar, and bass) and usually there's a couple of 12AX7s in the pre-amp stage and a few 6L6s or EL-34s in the power amp stage per channel. This is one small tube for six channels.

k.

Re:Only one tube?

[blair1q]

It's lower down on the page.

The tube is a dual triode, basically two tubes in the same package. It's got one or two cathodes, likely a common heater filament, two grids and two plates. The input signals go to the grids and the output signals are taken from the plates. Common cathodes would be fine, they'd both be connected to the same supply anyway. A common filament is an advantage, because it ensures the cathode(s) get the same heat, since thermodynamics plays a significant role in tube operation.

Answer your question?

--Blair
"Reading is fundamental."

Re:Only one tube?

[CaseyB]

I'd guess that it's got SP/DIF 5.1 output intended for use separate from the tube-amplified stereo output.

Re:Only one tube?

[blair1q]

2 tubes, main stereo signal.

4-8 channel sound is a combination of the two main channels and some mixing and layering. The two front main speakers still carry most of the sound, minus some of the center channel sound. The rear speakers and subwoofer carry only a small portion of the sound, and don't need to have the same tonal quality as main sound.

Multimedia and movie sound are far too fake, processed, and noisy for anyone to care.

So you're not going to use pure stereo for anything other than audiophile music.

The fact that this tube circuit is also there for movies is just a bonus point.

One last thing: THX is a measure of minimal quality, albeit a necessary one in a world in which minimizing quality cuts costs and improves profits. They've already defined THX-Ultra to create a standard for low-to-moderate-but-loud quality. Expect THX-hyperultrasooperdooper before you see real audiophile quality, but again, the compressed, cut-up, foleyed, looped sound they put on movies (especially the shrieking, groaning, grinding crap Lucas considers sound) will waste the value of that kind of equipment.

--Blair

Re:Where did the ISA slots go...

[TellarHK]

I've got two boards that're probably designs a year or so old, and neither one of 'em has ISA on them. However, they all have AMR slots... Like that isn't going to be the next thing to go. Dumb idea in the first place.

Analog Computing?

[lostchicken]

I was really hoping for this to be for analog computing.

In the field of chaos theory, and cryptography, and countless others, analog computing is great. To have an analog accelerator, much as one has a 3D accelerator, or floating point module, would be great. The tubes could be rewired on the fly, like an FPGA, allowing the programmer do all kinds of things. Imagine if the programmer could work in voltages, with chaotic effects giving true random numbers. Using this chaotic data, you could form clouds and other random events for games, perform neural network calculations and countless other things.

The analog systems helping the digital ones would be quite a revolution.

Re:Analog Computing?

[GoRK]

Uhm, dude, grab yourself a geiger counter and a lantern mantle and read this site: http://www.fourmilab.ch/hotbits/

Your PC is not a '59 Fender Bassman.

[tarvo]

As a muso who has always used Tube based amps for that rich warm tone that you can only get when those 6L6's and EL84's are glowing a nice red colour I know why you would want to do this as an audiophile. I just don't think it's very smart.

Here's why;

Heat - I never rest my beer on top of my amp, not because I'm afraid it will spill. I just don't like warm beer. Half-way through the first set and the top of my Bassman is warm enough to send my beer cool in a few minutes. And that's through 3/4" ply and some varnished covered tweed.

Heat - A mate of mine who does repairs on guitar amps has cursed the fate of many Mesa Boogie amps of the early - mid 90's, tube tone was no longer passe' but unfortunately, anyone that knew anything about engineering electronics for tube use had become passe. The problem was that the tubes sockets for the Mesa's were soldered right onto the main circuit board - after a few short months of club use these amps were toast! The tubes had caused enough damage to the main board that they had to be replaced. Leo Fender designed his amps so that the tubes were mounted off the main board, and still does to a certain extent.

Heat - Well kinda, guys, it's just not cool. If you really dig your tunes and are a true audiophile, you'll get yourself a device that is purpose built for the reproduction of music. Yeah, you're 'putey is kewl. But it's not one of these.

I do think that this board is kinda funny.

TUBES ROCK!!!

[Caractacus Potts]

If they are serious (which I doubt), then they would be using a matched pair of tubes, not a single tube. Of course, they could also be reverting from stereo to mono. Anyway, tubes rock! I've got about a hundred of them sitting around for various projects, none of which involve motherboards.

Ummm... why?

[jbf]

From the photo it looks like you're giving up two PCI slots for the tube and associated electronics, which are about as far away from the audio output as one could possibly place them. So you have to run the tube'd audio past all this noise, and they're not advertising balanced lines.

For my two PCI slots in the ultimate audiophile machine, I think I'd drop in a ProTools board, and hang a 24/96 or 24/192 interface off of it. The analog audio would then all live inside a nice shielded box with a good power supply (computer power supplies aren't real clean), and I can hang outboard gear off of that box.

Tubes are great for warmth and all, but there are much better places to put it. Like off the motherboard and in a separate shielded case. If they're serious about making their motherboards better for the audiophile, at least put a S/PDIF or ADAT out on the thing...

Re:Ummm... why?

[isaac]

From the photo it looks like you're giving up two PCI slots for the tube and associated electronics, which are about as far away from the audio output as one could possibly place them. So you have to run the tube'd audio past all this noise, and they're not advertising balanced lines.

According to HardOCP, that thing that looks like a power connector near the audio circuitry is actually the audio output header, so as least the signal isn't going quite so far on dinky traces.

Agreed about the external DAC, though.

-Isaac

Re:Ummm... why?

[Chris Johnson]

Ugh... try a real converter instead. Digi converters suck, and the recent ones suck so badly that they fall apart even when you just ask them to handle audio from a simple tape machine. They sound thin and small, and are so poorly designed that it sounds as if there's a bass rolloff when you try to do music signals. It measures flat with steady-state tones, but music isn't steady-state and the demands on the power supplies are VERY different from that.

I mean, do what you want- but your idea of running an outboard DAC is good, it'd be a shame to see you waste it on Digi converters, especially the recent ones.

basic electronics

[Anonymous Coward]

To recap what's said a bit further down, a normal computer power supply could not put out the voltage needed to even warm up such a tube (do you really want to wait an hour for your audio to get up to speed? Consumers are impatient; they want everything NOW, which is why they have big capacitors in TV sets for this so-called instant-on that we take for granted.)

As someone who's worked in music stores for years, and with computers even longer, i can say with some authority that a small onboard tube of the kind shown here (looks like a 12AX7) would be useless for output; you see this kind of thing more often in tube preamps for input, so it doesn't seem logical. others have noted the RF interference, and the fact that a *single* tube would only result in mono audio - a one-tube solution would be more suitable for an AM radio or a guitar distortion unit. I would point out the sheer size of the component (about 3 inches tall) and the fact that it gets as hot as a light bulb as factors that would mean *something* in the computer would start melting (even presuming the use of ceramic sockets) - it'll certainly put a damper on your overclocking.

When it comes to audio and computers, the best solutions are high-end external A/D/A converters- the kind that support multiple sample rate options (the higher the better). If you want tube "warmth," you're not going to get it from one measly, underpowered preamp tube; you'll need a good tube *power amplifier* - not for loudness, but to provide more headroom before distortion sets in. These are about the size of 4U rack units and start at $3000 a pop....check www.audiogon.com for some listings :)

More useful would be native support for super-high audio resolution formats like SACD; with over 100KHz frequency range it eliminates a lot of the audio artifacts present in 44.1KHz (current CD) audio, reproducing transient highs with exceptional fidelity, bringing back a lot of the "air" missing from consumer digital recordings. That and multi-channel ADAT Lightpipe i/o.....

Re:basic electronics

[unitron]

"...a normal computer power supply could not put out the voltage needed to even warm up such a tube..."

Well, actually it's current that heats up a tube, not voltage, although it's the voltage that shoves the current through the tube's filament. Depending upon design of the tubes filament, the voltage necessary to deliver the filament current (A+) can range from 2 Volts for some "nuvistor" itty-bitty little tubes once used in TV tuners to 35 or 50 Volts for some tubes intended for "hot chassis" radios and TVs that have the various tubes filaments in series across the AC line so that you can drop 85 Volts across a couple of tubes and use the remaining 30 or so Volts for some 6 or 12 Volt tubes.

Most of what are known as "receiving" tubes (tubes used in radios, TVs, and audio amps, including musical instrument amps, tend to use filaments designed for 6 or 12 Volts. If all the tubes in an amp use 6 Volt filaments and/or 12 Volt center-tapped filaments, you can heat 'em all with one secondary winding on the power transformer that they're connected in parallel across (sometimes with AC to DC rectification and filtering in between the secondary and the filaments).

Perhaps you were thinking of the tube's plate voltage (B+), which can run from 40 or 50 Volts up to several hundred. However, not only can you build a switching regulator on a motherboard to change 5 Volts DC to 3.3, but you can also include one that'll step up the voltage. It may not amount to a lot of amperage (current), but it doesn't have to. You can use a transformer on the tube's output to change high voltage, low current to low voltage, high current because power = voltage times current on both sides of that transformer, although a little bit of the power does get used up in the transformer (turns into heat). That output transformer also provides isolation from the high-voltage plate supply.

I only saw the top-down shot where you can almost fail to notice the tube, but it looks a little bit fat to be a 12AX7 or 12AU6 size envelope. I'd go find my old RCA tube manual and try to guess what they might be using, but it's old and falling apart (just like its owner :-), and doesn't need any unnecessary mileage put on it and besides I disremember just what it's currently buried under.

Re:basic electronics

[Elbereth]

I trust him a lot more than you, because HE works in a music store and can speak from authority! I doubt you can say the same, Mr. Smarty Pants.

Re:basic electronics

[unitron]

"...HE works in a music store and can speak from authority!"

You are, of course, correct. I merely speak from nearly 40 years of knowledge and experience.

Does the Case Have a Window to See the Tube?

[John Hasler]

"...wondering about the ability of a switched psu to properly drive a tube amplification stage..."

Five volts will make the filament glow nicely. That's all it will take to convince the tube enthusiasts that the sound is better. No need for the tube to actually do anything.

To be somewhat less sarcastic, a small switcher could supply 100 volts or so for the plate, or they could use one of the 12 volt tubes that were developed for car radios.

Re:Does the Case Have a Window to See the Tube?

[gaudior]

Brilliant! You are correct, Sir!

My thoughts..

[zeno_2]

At first I thought it would be a good idea, but I looked at it for a moment and I find it to be somewhat useless. Why not buy a sound card of some sort that has an optical out to a real reciever? The sound card they use on that motherboard is an AC97 sound card, pretty much bottom of the line basic sound card. They did do a lot of stuff it looks like to stop the noise problems, but does this sound chip put out clean enough signals in the first place?

I love stereo's, I used to be into car stereo's but now im more into home theater stuff. I enjoy a good system just as much as the next person. My computer right now is hooked up to a sony str-de825 receiver, paradigm phantom speakers, and a velodyne 12/15 sub. It thumps pretty good, and I can still hook my reciever up to my computer using an optical cable, but I need a pretty long one and they are expensive.

I tried looking at this motherboard to see how it all works, but it doesn't mention much. Does it just use headphone jacks for the speakers, or does it have some way of accepting speaker cable? They say the motherboard is about 215 bucks, without the tube amp it would probably be about 150 bucks im guessing, so its a cheaper way of getting sound out of your pc vs. the external reciever/amp route. Here is a quote from their site:

AOpen's hybrid AX4B-533Tube unquestionably is targeted to a very exclusive niche market - passionate audiophiles and extreme gamers who are interested in building their own ultimate entertaining PCs

Id say that most passionate audiophiles also have enough money to buy equipment that would satisfy a passionate audiophile. So, that is a 'very' exclusive market, broke passionate audiophiles. The same goes for extreme gamers who want to build an ultimate entertaining pc (whatever that is supposed to mean. To me this includes a real home theater system =)

Ah well, its something new, shouldn't knock it, its just not for me I don't think. Anyone here have the chance to see one of these in action?

Tubes=Distortion

[occamboy]

I'm a real live electrical engineer with a degree and everything. And, I listen to lots of music, mostly classical. And I have a pretty good ear -- I can often accurately identify the conductor when listening to a piece. Here goes: Properly designed transistor amps produce distortion that is below the threshold of audibility (0.1% THD). This is really easy to accomplish -- even $200 receivers routinely do it. Tubes produce very audible distortion, and they clip softly. I'm sure that it would be pretty easy to design a circuit to reproduce this distortion and the soft clipping for the fine folks who enjoy it.

Re:Tubes=Distortion

[Animats]

I'm sure that it would be pretty easy to design a circuit to reproduce this distortion and the soft clipping for the fine folks who enjoy it.

Very true. And there's a great story about it. Bob Carver, the amplifier designer, once took one of the much-touted High End tube amps into a test lab and characterized its transfer function. He then built a transistor amp designed to match the transfer function of the tube amp. In blind testing, listeners, even fanatical High End types, couldn't tell the difference.

It didn't sell.

So, partly as a joke, he designed the Carver Silver 7, the most overdesigned tube amplifier ever built. $25,000. All tube. Separate power supply, preamp, and power stage chassis. For each channel. Everything chrome-plated.

It sold. Got great reviews. "Amplifier of the Decade" from The Absolute Sound. Carver must have laughed all the way to the bank.

Re:Tubes=Distortion

[SanLouBlues]

The best makers of solid state tube imitations:
http://www.line6.com/main/main.cfm

But only insturment amps, not stereo amps.

this must be a joke

[Dr. Awktagon]

As other /.'ers have pointed out, this MUST be a joke. A single vacuum tube in an amplifier doesn't serve any purpose but as a heater (or maybe just amplifies the center channel??)

I could imagine using a few (maybe fake) vacuum tubes in a case mod, that would be very cool. Or maybe build the power supply with tubes?? Has anyone tried that?

Oh well. I wouldn't mind having a nice tube amp OUTSIDE the computer for listening to MP3s .. it might fend off the digital noise of those 128k encoded MP3s.

What I really need to do is replace the 21-inch vacuum tube I stare into all day with a nice flat-panel model...

They're all harmonics!

[Mr Z]

Absolutely, the thing is that tubes distort harmonically while solid state amps tend to distort rather dissonantly and horribly.

Huh? They're all harmonics. Tube and certain kinds of FET (field effect transistor) based amps have a "soft limiting", so when they get close to clipping, they tend to generate even harmonics. Three of the first four even harmonics are exactly 1, 2, and 4 octaves away (2nd, 4th, and 8th harmonics), and so this form of distortion tends to be more melodic and pleasant. The 6th, 10th and so on aren't so melodic, but since the amplitude of the harmonics drops as you go to higher harmonics, you're ok.

BJT (bipolar junction transistor) based amps (and other types of solid state amps) tend to clip rather hard. No soft-limiting, they stop right at the rails. This clipping action creates a boatload of odd harmonics. These harmonics are fairly dissonant, giving the harsh sound most people complain about.

But they're all harmonics.

--Joe

Re:They're all harmonics!

[mesocyclone]

Errr.... harmonics at clipping are all fun and that, but only if you have one sine wave in your amplifier. With real music, you have lots of signal in there. Then, any kind of nonlinearity, whether tube or solid state, will produce intermodulation which consists of sum and difference frequencies. Intermod is infinitely annoying and the real problem with distortion in amplifiers.

The math of this is simple - and applies to RF as well as AF. Take two of the signals in the systemm and approximate them for as sin waves. The nonlinearity can be modeled as a power series, so you have terms of the form:

f(a,b) = A*(a + b) + B*(a + b)^2 + C*(a + b)^3...

Substitute

a=sin(w1*t+phi)
b=sin(w2*t)

And do the trig and you can see that you end up with all sorts of neat frequencies such as

w1-w2, 2*w1-w2, etc.

Now, instead of f(a,b), imagine f(a,b,c,d,e,f,g...)_ and you can see the mess that intermodulation makes. It basically mixes (in the frequency domain) all of the signals AND all of their harmonics in all possible combinations!

Tube amplifiers *do* sound different because their distortion curves are different than solid state amps. Why audio "purists" prefer one distortion curve to another is what I don't understand. What I want is minimal distortion overall!

But then, audiophiles also buy gigantic cables because they imagine that their speakers will sound better attached to them... etc.

Technical note: The coefficients on the various terms of the power series tend to go down with the order of the term. And, some configurations approximately cancel out all odd or even terms.

Re:They're all harmonics!

[zerocool^]

I can't believe this isn't modded +5 yet (1AM est). Usually people that bust out equations on slashdot get modded up instantly. In fact, if i had moderator points, i'd probably glance at it, say "I don't understand that", and mod it up, because anyone that writes something that I don't understand is Insightful, right?

This all looks legit, from the 5 times I attended my Engineering Fundamentals class before switching majors, i recognize some of this.

But honestly, you could be bullshitting the entire thing, and about 4 people on slashdot would know it.

I didn't know there were this many audiophiles that read slashdot.

On a side note, i used to sell stereo equipment at best buy, and i was always skeptical of the "high end thick" cables (monster cable). I wondered how good it could really be if we paid mabey a buck more for it, but charged 35 bucks more for the RCA cables than the generic RCA cables, wondered where the extra quality was comming from if it was that profitable.
Then one day, an electrical engineer came in and flat out proved to me with numbers, resistanace, etc, that you don't need anything more than 16 gauge wire for anything any amp we sold at best buy could put out into any pair of speakers we sold.

~Will

Re:They're all harmonics!

[sigwinch]

But honestly, you could be bullshitting the entire thing, and about 4 people on slashdot would know it.

I'm one of the 4. ;-) The description of how nonlinearity causes "interesting" intermodulation in complex signals is spot on. BTW, RF engineers deal with multi-signal intermodulation all the time (cell phone base stations, cable TV amplifiers, etc.)

Then one day, an electrical engineer came in and flat out proved to me with numbers, resistanace, etc, that you don't need anything more than 16 gauge wire for anything any amp we sold at best buy could put out into any pair of speakers we sold.

And even if it did make a difference, heavy speaker cable should only cost a little more than jumper cables. You could even make an (almost) impedance-matched 8.3 ohm coax by putting six 50 ohm coaxes in parallel, and it still wouldn't cost as much as the ridiculous audiophile cables.

Ding Ding Ding....

[Silver222]

We have a winner!

The most common argument the tube lovers trot out is that the best guitar amps use them. They seem to forget that when you are listening to music, you want something that accurately reproduces the sound on your source, you don't want something that changes the source.

"Audiophiles", flame away.

Re:Ding Ding Ding....

[scumm]

I'm not a semi-serious guitar players, I'm a pretty overly serious guitar player, and these guys are almost entirely correct.

Since the late 70's (for the most part - some have never bothered to change) venues have tended to use solid state amplification for sound reinforcement, for the reasons listed above - more efficient power consumption, more reliable, etc.

For guitars, tube amps just sound better. Digital modelling, etc., all try to REPRODUCE the sound of a tube amps, not best it. That's fairly telling. The reasons tube amps sound better for guitars are varied, but are mostly centered around overdriving the amp. The distortion comes on very smoothly as you roll the volume up, and responds to dynamics much better.

For home stereo? Some of the best audiophile home stereos I've heard have been tube (mid 70's Marantz gear), and some have been transistor (late 70's Marantz gear). But tube amps are just NOT cost effective anymore, and almost all of the supposed advantages are just audiophile snobbery.

Another problem with current tube amps is the downright sorry state of tubes. You have to search REALLY hard to find a really high quality 6L6, 12AX7, or EL34 nowadays, and those are the most common used in amplifiers. Hell, the only place to find really high quality ones, like Mullards or Telefunkens I've found is eBay. And they're expensive.

Remember, audiophiles don't listen to music, they listen to noise, and therefore souldn't be taken seriously.

Possible? Yep.

[Mark19960]

How? you ask?
Easy. they state they have a switched mode power supply on board.
for those that dont know, you can step up that meager 12 volts to 5,000 volts if you wanted.
also, they state that it is a DUAL TRIODE tube.
this may very well NOT be a joke. it can be done. issues I have with this setup include noise, heat, and if the tube is socketted.. or available if it dies down the road. todays power supplies are better filtered than the supplies of yesterday, and im sure that the tube is better made, as well.
I may want one just for the hell of it, you have to admit... its pretty damned neat

AC97 was Re:its a waste!

[foonf]

BUT useing the ac 97 codec??? i have never heard very good sound out of one of them, and i have always found it to be just that codec, if they would do it with a good audio chip, it would be much better.
just my thoughts...

Really, what kind of sound card do you have? If you are using your computer for high-end audio production or music composition and are talking about truly high-end sound cards, that statement has some merit, no commercial AC 97 codec can probably produce what you would consider "good sound".

Presuming this is not the case, its probable, unless you have in fact a very obsolete or low-quality sound card, that it in fact uses an AC 97 codec similar to those used by many onboard sound interfaces. AC 97 is just a generic standard defining an interface between the sound codec (which actually produces the sound) and the controller (which attaches it to the bus, and provides DSP and synthesis functionality is some cases). Even expensive consumer sound cards like the Creative ones and the Hercules Game Theater use codecs which are AC 97 compatible. Most of the criticism of motherboard audio either has to do with the lack of features (which given that even expensive consumer sound cards don't do hardware MIDI synthesis anymore, isn't terribly relevant except for video game players) or the poor sound quality (which doesn't have to do with the AC 97 standard per se, but low quality of individual codecs and poor electrical design. None of these things are universals, I have a notebook which uses the AC 97 codec interface of its motherboard chipset, but a Crystal codec (identical to the one used by most of the CS4630 cards like the Santa Cruz, Game Theater, etc.), and produces very nice output.

And also, on this mobo...

[Lobsang]

Instead of the traditional CD-ROM, you have a vynil LP player, a cassette players instead of a disk drive and a round tube black & white zenith TV as the monitor. The keyboard is clickety clackety and mechanic, with round keys.

And the commercial is something like:
"Easy to Use, easy as Hell"
:)

The RIAA put them up to it...

[Jah-Wren Ryel]

In their never-ending quest to turn back the clock, the RIAA has announced their latest tool to fight music piracy on the high seas and in your home - vacuum tube based soundcards. Not happy with preventing digital SACD and DVD-Audio playback on consumer stereo equipment much less consumer PCs, the RIAA is now forcing all motherboard manufacturers to support only the oldest functioning technology for audio playback known to man.

Hillary Rosen was quoted as saying this hardware program will finally end the Napster menace once and for all.

Pictures

[CaptainSuperBoy]

at HardOCP

Re:Pictures

[n6mod]

Ahh, excellent link. From the photos, we can see that the tube is a Sovtek 6922. Google tells us that thetubestore.com calls the 6922 "Sovtek's premium version of the 6DJ8." Which everyone should recognize as a dual triode. Data here tells us that it has 6.3V filaments (perfect for coexistance with any 25120's that may be required by future DRM schemes), wants 90V B+ (plate voltage) and has a max Plate Dissipation of 1.8W.

This is a preamp tube, which is appropriate, actually. Get those nice GloFET harmonics and then feed it to some decent SandAmp for actual power.

Interesting concept. Twisted, and I don't think I want my preamp tube in the same faraday cage as my P4, but it is interesting.

-Z

Re:Pictures

[n6mod]

For the less tube savvy out there, that means it is a preamp that can drive six channels.

Uhh, no. It's a dual triode. That means it has two sections each of which have three electrodes. Those three electrodes are Plate, Grid, and Cathode, which map roughly to Emitter, Base, and Collector. (I think...it's been a while) Actually, I suppose Source, Gate, and Drain are more appropriate, this being a GloFET.

In any case, there are two devices, not six, so you get two channels, not six. In fact, I'm pretty sure the 6DJ8 was designed for balanced operation, not stereo. For the less tube savvy out there, that means it was designed for one channel, not two.

Firebottle, but not Firewire?

[n6mod]

Now, I was almost ready to buy one of these, GloFET and all, but there's no Firewire. And since that lovely firebottle takes so much room, there are only 3 PCI slots... One for FW, One for the HD tuner, One for Gigabit, One for SCSI... oops, no more slots.

On the flip side, I've never been much for case windows...but this board NEEDS a window!

-Z

Lee De Forest

[FunkyRat]

You're thinking of Lee De Forest who was the inventor of the audion tube, the tube equivalent of the transistor. De Forest is also one of the most fascinating men of the 20th century, one of the last great lone inventors whose invention spurred development of everything from the long distance phone network to the first digital computers.

If you ever get a chance I highly recommend reading Tom Lewis' book Empire of the Air which profiles the three men probably most resposible for the modern age of communication: Lee De Forest, Edwin Howard Armstrong and David Sarnoff. IIRC, Ken Burns also did a documentary based on the book for PBS. These are truly three of the most interesting, and in many ways, most tragic men whom have ever lived.

Obligatory pun jokes...

[tcc]

VACUUM tubes? isn't that the new name for Rambus memory that sucks even more?

Expensive Tubes / Crappy Codec?

[Ween]

Why would they go to so much trouble as to put tubes on a motherboard for quality audio output then use the super crappy Realtek ALC650 AC'97 CODEC. Maybe their engineers know something I dont, but that was a big dissapointement when I saw it.

Re:Expensive Tubes / Crappy Codec?

[mindstrm]

Doesn't ac'97 specify a 20 bit architecture for sound processing? is this not even higher than what is coming off a CD?

old school

[trb]

It seems that their server is slashdotted, perhaps it too is built using tube technology.

Re:old school

[geekoid]

But if they where using tube technology, at least it would sound nice as it went down.

How they came up with this idea...

[evilviper]

(Sitting around one day)

Bean counter: "You know, people are only willing to pay about $6 for a soundcard. How can we get back to the good old days when people spent great gobs of money replacing high-priced disposable components?

Engineer: Let's stick a tube in there. Everyone likes the nice fuzzy sound that comes from tubes. Hell, that's why "Turbo Bass" and equalizers are so popular.

Bean Counter: Sounds good, as long as we get the most outlandish design, so they can't just get parts or repairs from anywhere. We want them to come back to us.

Engineer: Got it!

minor spelling correction

[Doktor Memory]

As an owner of a tube headphone amplifier

You misspelled "sucker." Hope this helps, have a nice day.

Re:New disk drive also in development for this boa

[jpmkm]

what is even funnier is that cds are digital and lps are analog

Single tube stereo-

[rMortyH]

Hey-
Like IC's, there are usually more than one device in a single package with tubes. We're probably looking at a dual triode. Could (should) be quad triode, but I seriously doubt it.

It's never gonna sound much better than the D/A, which is probably a runofthemill 44.1k by 16bit job, which just isn't all that great, especially with only one triode per channel instead of two.

SO it's a sales gimmick. But, it's a DAMN GOOD ONE and I'd like to see more of this and I think it will succeed as it should!

More crap like this, please! Give me swing meters and magic-eyes and nixies! Bring it on!

=Rich

PCI?

[Perdo]

I can see it now:

Soundblaster Fried! X-audiophile

or a new port instead of AGP, you can have AAP (Accellerated Audio Port) or a sound card that uses the AGP Port for audio while video is relegated to the PCI bus. I think ATI might like this last option since they still make PCI versions of their cards while Nvidia is exclusively AGP.

Speaking of which.. Can the AGP port be used for applications other than video? Could a 10 gigabit NIC use the AGP bus? 16 channel input 144khz audio A/D converter card? What other applications could use a 2034Mb/s 8x AGP bus where 64 bit 66mhz PCI's 533Mb/s and PCI-X's 1024Mb/s fails?

And in other audiophile news...

[marhar]

CDR Sound Review tells us how various brands of CDRs stack up for different types of music:
"Maxell 700 MB silver top for more detailed highs, Maxell Music gold for a fatter, more solid mid-to-bottom."

Re:And in other audiophile news...

[mindstrm]

Someone forgot to tell the guy that the color is totally irrelevant, and has nothing to do with the recording surface where the laser actually works.

Ah, I get it now!

[kfg]

Forgive me for a momentary metal denseness.

You are laboring under the misaprehension that I'm a punk kid who just posted a mindless anti Apple computer crack intending to imply that a Machintosh isn't a "real" computer.

Far from it, if I had been I couldn't have posted what I did in the manner that I did.

You see, I neglected to take into account that many of the more "youthful" of the /. audience wouldn't be aware of just what a Macintosh really IS and that if there were no such thing as a Macintosh computer I *still* would have made my orginal post, which would have still made sense.

Macintosh, as it happens, was a, ( some would say THE), premier manufacturer of tube amplifiers for commercial and audiophile customers, as much a household word in their day as Teac is now.

My orginal post was intended as a somewhat wry and yes, ironic, comment on the convergence of "media devices," hightened somewhat by the fact that there are audiophile tube amplifiers AND sophisticated home computers named Macintosh.

In my own home the "stereo" and "TV" sit in the corners acting mostly as dustcollectors, as I use my "computer" for nearly everything, including as a "radio" and "tape deck."

*Ironicly* I'm posting using Windows right now because my Mac isn't connected to the network at the moment and my Linux X-server has crashed and I'm not in the mood to reconfigure everything to make one post using Lynx.

So, anyway, if I'm guilty of anything it's of being too opaque in my reference and too dense to realize it.

Hell, as implied above I *use* a Mac, ( and used to use a Mac).

KFG

Interesting case mod for this tube ...

[ProfMoriarty]

take the tube off of the MOBO ... and wire the socket that is left to a new socket on the top of the case.

When the audio is working ... it'll make the computer look like it's thinking ... (lightbulb glowing)

:)

ObRef to The D

[tswinzig]

It seems that their server is slashdotted, perhaps it too is built using tube technology.

JB: "Get the scientists ... working on the tube technology, immediately."

KG: "Tube technology..."

Switched power supplies are fine.

[Futurepower(R)]

"... while simultaneous wondering about the ability of a switched psu to properly drive a tube amplification stage cleanly."

This shows ignorance of electronics. (No problem, everyone is ignorant of something.) If "psu" means "power supply unit", there is no problem. Switched power supplies output constant DC that is indistinguishable from the DC from transformer-rectifier-capacitor supplies, if both are regulated equally well.

The old style supplies sometimes had huge capacitors that would provide energy for peaks in the output of power amplifiers. Switched power supplies could use huge capacitors for the same purpose, but in practice it is easier just to design the supply so it can provide all the power needed for the peaks.

Re:Switched power supplies are fine.

[Futurepower(R)]

In a well-designed system, this should not be true. Switching power supplies switch at 100,000 Hz typically, or above.

It is important that the high-power system be isolated from the low-level signals.

Big joke.

[Futurepower(R)]

It all seems like a big joke to me.

It goes with 100 to 1 data compression and electronic super cooling.

There are people who like science, but don't particularly want to know anything about it.

Don't be a player hater

[DrSkwid]

who would spend $700 on a video card to give an extra 20fps (total of 150fps) on their 80hz monitor.

Nice try but the fps plays an intrinsic part of the control system, it's proportional to the latency. At lower fps the machine cannot respond to mouse events as soon. So having a high FPS is a metric to how well the machine will respond overall.

Also, people use FPS in Quake3 as a guide. Okay one can say 'I got 3547' on 3dMark but Quake3 fps is something people can directly understand. Remember that play many games and not just Quake3. For instance I just got a GeForce4 ti4600. I get 220 fps in Quake3 (@1280x1024x32 :) with the default config but in Dungeon Siege I get 10fps @ 1024x768x32.

I've never heard of anyone spending $700 for 20fps! (but that's not to say it's impossible)

As for liquid cooled, if I could be arsed/afford it I'd buy it and take a 3% performance *decrease* just to show it to people at LAN parties.

Don't be a player hater. The world would be a sadder place if people didn't play.

Correctomundo!

[Jeppe Salvesen]

Sound cards need to have digital output, so that we can hook our computer into our THX-compliant monster system.

Seriously, though, an external DAC unifies the sound from your DVD, MD and PC.

CD Player in BIOS

[p3d0]

Now this is cool:

Another interesting software feature that will be shipped with the board is CD Player software. While this does not seem to be anything new, AOpen's solution can run the CD player without booting into a Windows OS. The CD Player loads immediately after the BIOS.

Re:Can you explain this to me ...

[markhb]

• How exactly is a *VACUUM* supposed to conduct heat??
  
  
• You've clearly never seen a vacuum tube device in operation.
  

Not to mention, lived on a planet heated by a star which is c. 92 million miles of near-vacuum away.

Thanks for propagating the myth.

[mindstrm]

Look. For a guitar amp, I can see it.. the tube amp is as much part of the insturment as the guitar. It definately does mess with the sound.

How ever, as with many things that 'audiophiles' think, tube amps are NOT better than solid state at reproducing sound. Tubes mess with the sound. Yes, they sound good. But not as accurate as a good solid state amp.

Now, I'm not saying there aren't extremely high quality tube amps.. there are. But companies make these things so they can sell them at rediculous prices to audiophiles who mistakenly think tube amps are more accurate.

Guess what. The recording engineer who mastered the thing didn't use a tube amp.

It's not a hoax...

[HardCase]

Chrisd's right on about the power supply, valves have pretty demanding power requirements, and the voltage is much higher (300+ volts is typical) than what's normally present in a PC.

It really wouldn't be much of a problem to step up the voltage to 180v-300v. Obviously there wouldn't be a tremendous amount of current, but since this tube is designed to drive the output of a preamplifier, little current is required.

Also, most tube amps require output transformers, which is noticably absent from the photo.

There are scads of output transformerless (OTL) amps on the market. They're designed to drive low impedance loads. Even so, this is a preamplifer, so it will be driving a relatively high impedance, thus no output transformer is required.

Thirdly, there's only one tube! Presumably, if they are really after the audiophile market, it would at least be a stereo amplifier.

This is a dual triode tube, perfectly suited for stereo. As I recall, it would work great as a common-cathode amplifier.

Not to say anything about the noise problems present near high speed digital circuits.

That's where I'd be concerned. I think that this is really nothing more than a gimmick. I suppose they can say that it's aimed at audiophiles, but in reality I think that its true market will be for the case modding crowd to take advantage of the "gee whiz" factor.

This is bunk.

Never underestimate the power of a marketing department.

-h-

Re:Audiophiles, do a blind test

[mindstrm]

Yup.
Because many audiophlies have average hearing.
If anything, they may be a bit more practiced.

THe mind is a powerful thing. It's hard to listen to two pieces of equipment and compare fairly if you know that one is supposed to be better. The mind plays tricks.

And regarding cabling...

Those audiophiles who blow amazing amounts of cash on their setups often have far better equpimetn than the sound engineer who produced the album in the first place. Now, given that, what is it exactly that they are trying to reproduce exactly? The mastering engineer's equipment? You can't, you don't know what it was.
The original performance? YOu can't, the mastering engineer has already tweaked the recording repeatedly to get it so it sounds the way HE wants it to sound on average equipment.

Ah.. but that's not the point.

[mindstrm]

The point is that it has a tube on it so they can jack up the price and sell it to wannabe audiophiles for lots of greenbacks.

Oh geez...

[Moridineas]

As an owner of a tube headphone amplifier I applaud AOpen's move to accomodate the high-end audio enthusiast

Hooray!! You're amplifying crappy on-board audio!! But who cares, it's a TUBE AMP.

Capitalizing on Nostalgia

[cwilkins]

The next AOpen mobo features:

More Tubes!

Coal Fired & Steam Powered!

Comes in 330lb "Floor Standing Console" case, with beautiful oak finish and mother-of-perl inlay!

Options:

5 inch Round-Screen B&W Monitor (shipping weight: 190lbs)

Latest High-Tech "Keypunch" style keyboard (your neighbors will hear you type)

Mouse

Mouse Food

Preorder yours today!

And remember: Real Computers Glow in the Dark! (apologies to fellow hams)
-

Re:Small point

[geekoid]

because, if its not Scottish, it's CRAP!

I like tubes because...

[geekoid]

...with out them, I couldn't cook my hotdog under 30 seconds.
and I'd have to use a crappy flatscreen.(i.e. all of them).

Not to mention, that with out them I wouldn't know that She'll give you ev'ry penny's worth
But it will cost you a dollar first.

Really.

[mindstrm]

So you mean a computer at home is not the same as home audio...
and you assume tht everyone hookes their compute rup to one of those subwoofer/2 tiny speakers deal?

Interesting.

This is not a tube amp! It's is a preamp tube.

Re:The Hybrid Revolution is underway!!!

[mindstrm]

A guitar amp is a different story.. the amp is part of the instrument. That's sound production, not reproduction.

I don't mind the heat...

[JCCyC]

...because Tubes Rock!

Re:huh?

[mesocyclone]

A comment... The magnetic interference will be the same regardless of the size of the wire (within limits). So larger wire has no effect on that interference.

As far as supplying power to the speakers, you simply need wire large enough to carry the peak currents, and low enough resistance that the impedance (hopefully resistive) of the speaker is quite low compared to the resistance of the wire. However, even if this is not the case, you do not increae the distortion (as long as the amplifier is not mismatched), but rather simply reduce some of the power available to the speaker which does not produce distortion, but rather produces simply slightly less power. Everything else you say about speakers is simply irrelevant.

Thus if you are running, say, 1000 watts RMS (enough to break your ears easily), and the speakers are 4 ohm impedance, you have an average current of 16 amperes. This current is easily carried by normal house wiring for a hundred feet! So no problem with the wire melting.

Now, to make sure you don't loose a significant amount of power to resistive heating in the wire, let's say that you are willing to sacrifice only 1/10th then you need the resistance of the wire to be less than 1/10th the equivalent resistance of the amplifier - i.e. you need it to be less that .4 ohm. If your wire is 20 feet long, then it can be as small as 19 gauge (convenient, since you need 18 gauge wire to carry 16 amps without getting too hot). So by this analysis, 18 gauge (smaller than "zip" cord - extension cord - wire).

Another reason that you failed to mention is the impedance of the wire. If the wire is not purely resistive, it will cause a rolloff with frequency - the pwr to the speakers will decline with frequency. Here is a table showing the rolloff at 30KHz for a 20 foot cable of varying widths:

Wire Gauge ... Diameter inches ... Rolloff at 30 KHz(dB
?... 10 ... 1.8dB
?... 2 ... 2.18dB
1... .29 ... 2.5dB
10... .1 ... 2.7dB
18... .04 ... 2.9dB

Finally! An effect that we can measure of small wire. But note: with a wire 3 inches (!) in diameter, you have almost as significant rolloff as you do with a wire of .04 inches in diameter. Not a major effect, in other words.

But... if you really care about the difference in rolloff between 1.8dB and 2.9dB, you are much better off with 10" WIDE cable than big fat cables.

Of course, a much simpler and perfectly adequate approach to this is to use an equalizer (very simple in this case) to compensate for the inductive rolloff.

The one thing I learned from this /. post...

[gosand]

The one thing that I learned from the slashdot post was...

audiophiles are DORKS! :-)

Man, I thought some of the other discussions on here get a little in-depth sometimes, but I can't understand a damn thing that most of these people posted. Is all that crap in your heads all the time? How do you function on a daily basis, when you understand how your ear is hearing sounds at a microscopic level?

LP-ROM

[dillon_rinker]

The music industry is likely to squash any attempts to create or market an LP-ROM. Check out this site.

Re: anode voltages

[unitron]

Weren't most aircraft electronics from "back then" designed for 400 Hz AC (not Volts, cycles per second, as opposed to 60 cycle household current)? The higher frequency was so that transformers and filter chokes could use smaller, lighter iron cores.

Re:Audiophiles, do a blind test

[Jeff DeMaagd]

Well, I bet audiophiles probably run a spectrum rather than be fit into a neat little category. There are smart ones that let their ears do the listening and then there are ones that will pay more simply because they are told that it is better by a salesman or an ad.

I don't think I'm an audiophile, but I generally demand something just a bit better than what Best Buy offers for speakers and the reciever. I ended up getting a speaker set that was the cheapest that the hi-fi store sold, and quite frankly I haven't been let down, either in the listen test or at home.

tube testers and Wire recorders

[hawk]

>know anyone who wants a professional tube tester?

Me, but I already have one :)

Know anyone who knows how to fix a wire recorder?

This thing uses a five or ten pound "cassette" to hold the wire spool it uses for audio recording. I even have a second (but broken) cassette for it.

hawk

instant replay

[hawk]

ABC originally pulled off INstant Replay by using computer hard drives as analog devices . . . I forget how much time they held (not a lot!), but it was pretty much just an analog recording on the disk surface, allowing them to instantly go back a few seconds . . .

hawk

High Fidelity Tube Amps versus Guitar Amps

[BigBlockMopar]

Agreed!

For guitars, tube amps just sound better. Digital modelling, etc., all try to REPRODUCE the sound of a tube amps, not best it. That's fairly telling. The reasons tube amps sound better for guitars are varied, but are mostly centered around overdriving the amp. The distortion comes on very smoothly as you roll the volume up, and responds to dynamics much better.

A very big point with guitar amps is microphonics. Since the amplifier chassis tends to be built into the same cabinet as the speaker, all the tubes are vibrating with each note. This does all sorts of neat things to the sound, since the elements (plate, grid(s), cathode) are all vibrating with respect to each other. In REproduction, microphonic tubes are a very bad thing. But in a guitar amp, the amplifier is absolutely part of the instrument.

Some of the best audiophile home stereos I've heard have been tube (mid 70's Marantz gear), and some have been transistor (late 70's Marantz gear). But tube amps are just NOT cost effective anymore, and almost all of the supposed advantages are just audiophile snobbery.

Agreed. Most of today's tube fascination is unjustified.

A tube output amplifier is *not* a high fidelity device in this day and age - by using tubes, you're forcing yourself to deal with the nonlinearities in the behavior of the tubes and, more importantly, of the output transformer which impedance-matches the tube to the speaker. Building a transformer to be a "straight wire with impedance matching" at any sort of power from 20Hz to 20kHz is non trivial, from the core up. (Power transformers from 50/60Hz are big and heavy, full of laminated iron sheets. Transformers for 15kHz (TV flyback transformer) are ferrite-cored. Hugely different magnetic properties of the core, and both of those devices are *within* the audio range!) There is no logical or rational reason, in this day and age, to use a tube output stage in a non-guitar amplifier.

However, in small signal stages, things are different. Since tubes run at higher voltages than comparable solid state components, induced noise is less significant. If your audio signal is floating around on a DC offset of 140V and you're inducing 500mV of noise into it, that's a hell of a lot less obtrusive than the same 500mV of noise induced on a 12V offset. Never mind that the interstage amplitudes also tend to be higher. There are a couple of issues, here, though. Tubes are larger, meaning that they have larger areas of conductors to pick up noise than, let's say, a surface-mount MOSFET on a ground-plane PC board. And vibration is strictly verboten; we don't want to color the music.

And tubes amplifiers tend to have high input and output impedances, which makes them ideal for pre-amp stages.

Audiophiles like tubes for the wrong reasons. If tubes add "warmth" to your music, the amplifier is probably driving them too hard and you're attenuating the high end (ie. poor design). But if a tube amplifier is indistinguishable from a semiconductor amplifier except that there's less hiss, then the tubes are doing their jobs.

As I told an "audiophile" once, they don't use Monster Cables in the recording studio... Balanced line XLR. Good engineering is always better than cheap crap sold in shiny blister packs. :)

Re:High Fidelity Tube Amps versus Guitar Amps

[BigBlockMopar]

Funny thing, though - Monster Cable is pretty crappy cabling, but for guitar cables, the D'Addario PlanetWaves cables are actually exceptional. And they come in shiny blister packs (or rather, you CAN buy them in shiny blister backs, or in braids).

Feh. I'll stick with the stuff the pros use: light duty work (recording studios, etc.) is HPN heater cord. About 6 cents per foot at Home Depot. :)

Rigging arrayable speakers for use in stadiums (rock concerts), we'd run tin-plated copper stranded distribution cable (pole-to-house wire) for long runs and 8 or 10 AWG 2-conductor jacketed cable. The distro cable was used primarily for heavy metal concerts at smaller venues like the 50,000 seat SkyDome. [grin] Anything bigger and you'd fly the amps in the rigging, too.

Re:MOSFETs==Transconductance amplifiers

[fmaxwell]

If tubes & FETs work on the same amplification principle -- voltage in begets current out (transconductance)--
why not use efficient, low-cost FETs?

Many people do use FETS, MOSFETS usually, for just that reason. The MOSFET, as a direct-coupled output stage, does not exhibit the soft clipping of a tube amp's transformer output.

You also get into the concept of "euphonic distortion" -- distortion that people like. For instance, the tight bass associated with a high damping factor, direct-coupled output actually does not sound as good to some people as the looser bass from a transformer output.

The above just a few examples.