AAC vs. OGG vs. MP3

asv108 writes "Yesterday, Apple unveiled their new music service claiming that the AAC format "combines sound quality that rivals CD." Here is a little comparison of lossy music codecs, comparing an Apple ripped AAC file with the commonly used MP3 codec and the increasingly popular OGG codec. Spectrum analysis was used to see which format did the best job of maintaining the shape of the original waveform." Wish they had WMAs in there too. And for the spoilage, it looks like OGG comes out on top.

Comments

Hard To Tell Difference

[Ffynon]

I've got a nice pair of Bose headphones, and I listened to an Apple Store AAC file and an OGG version of the same song. I don't consider myself a real audiophile, but it's damn near impossible to tell the difference between the two; though I can definitely hear the improvement from MP3 to AAC or OGG.

Re:Hard To Tell Difference

[Anonymous Coward]

how are you encoding your mp3s?
try lame with --alt-preset extreme
can you tell the difference then?

Re:Hard To Tell Difference

[glesga_kiss]

To do a true test, you need to encode the files, decode them to PCM wav format, then burn to an audio CD.

Then, you have to do a blind test with all of them. You also need to use a variety of source material, because different genres of music compress better under some encoders.

Re:Hard To Tell Difference

[afidel]

Well your first problem is your headphones, they are distorting the crap out of any music source, go get some Sennheisers, they start around $60 for a good pair of open cans. Also if you are using anything but Fraunhoffer or better LAME for mp3 its just not fair. Btw, I've found high range problems with OGG that were not present in my Lame mp3's (I did A,B,C blind tests on a variety of samples and found a couple of problems with OGG which I reported with samples). AAC at 128kbit sounds like trash just like every other codec at 128, get around 200kbps VBR or 256 CBR and thats where the differences start to really show up (ok they show up at the very low end like 90kbps too but I don't even want to think about that)

Re:Hard To Tell Difference

[blixel]

To do a true test, you need to encode the files, decode them to PCM wav format, then burn to an audio CD. Then, you have to do a blind test with all of them. You also need to use a variety of source material, because different genres of music compress better under some encoders.

If you have to do all that to tell the difference, doesn't that kinda tell you something?

Re:Hard To Tell Difference

[Vann_v2]

That's there value in ruling out variables when trying to objectively compare things?

Re:Hard To Tell Difference

[BrokenHalo]

You would probably notice the difference if you try the test with certain kinds of classical music...

Even then you would probably have to be selective. Rich orchestral works (say, Janacek, Mahler, Sibelius) won't show an obvious difference, but something more spare (e.g. Debussy string quartet or a good recording of baroque strings) will show a big difference that should be evident even on poorer quality equipment.

Re:Hard To Tell Difference

[slothdog]

To do a true test, you need to encode the files, decode them to PCM wav format, then burn to an audio CD.

Then, you have to do a blind test with all of them. You also need to use a variety of source material, because different genres of music compress better under some encoders.

Or you could just use ABX. That's actually the de facto standard for comparing audio compression. (See HydrogenAudio.)

Re:Hard To Tell Difference

[PhilHibbs]

No, it should tell you if you have to go through that much work to perceive the difference that you shouldn't bother. Just enjoy the music.

First of all, different people have different hearing acuity, so if I notice a slight difference on a hifi deck, it might be noticeable to someone else on PC speakers. Secondly, the difference might not be enough to notice on a conscious level. Thirdly, the music that I do the test on might only show a slight difference that only shows up on hifi, but other music might show a greater difference.

When you're doing comparisons, you have to eliminate as many variables. That's why there's an ISO standard process for making a cup of tea.

Re:Hard To Tell Difference

[bluepinstripe]

Please note: the post said, "To do a true test [. . .]" It did not say, to tell the difference.

Re:Hard To Tell Difference

[Wakko Warner]

speaking of "sound quality" a 5$ headphone is on par with a $100 headphone.

Your $5 crack clearly isn't on par with $100 crack.

I can't believe how wrong people on slashdot can be sometimes.

- A.P.

Re:Hard To Tell Difference

[squiggleslash]

That may be good for you and I, but a true audiophile can tell the difference between a pressed CD and a CD-R... ;-)

Well, I'm off, I have to get some gold cables.

Re:Hard To Tell Difference

[glesga_kiss]

so if I notice a slight difference on a hifi deck, it might be noticeable to someone else on PC speakers.

Highly doubtful.

I think there was a typo there. I reckon he meant to say that you might not be able to hear the same difference on PC speakers. As the fidelity is less, that makes perfect sense.

My original post way up the chain was mainly because I've heard so many people compare an mp3 on their PC speakers/headphones through an on-board soundcard to a CD played on their HiFi. That's just bad science.

If you care that much about music, then why not just listen to CD's or pure WAV form? Why mess with lossy compression at all?

Because when it's done properly, the "lossy" issue is not a problem, as you will have already decided what your minimum requirements are. I use the r3mix mp3 encoder preset (site seems to be down, very odd), and I get great results through my AWE64 soundcard hooked up to a separates system.

The open-source cd -> mp3 ripper/encoder CDex has an encoder option to use this quality preset. Ideal.

Re:Hard To Tell Difference

[Pieroxy]

The problem in your test is that if you know which file you're listening at, you're just not fair in your comparison and by listening several times, your brain just makes you hear stuff that is just not there.

A test was made where people would listen to two WAV file, one supposedely was an MP3 (that was expanded to a WAV). 25% of the people could hear a difference between the two WAV files where they were actually the same...

Re:Hard To Tell Difference

[swagr]

>go get some Sennheisers

Unless you plan to spend more than a couple hundred, do yourself a favour and get some Grados.
http://www.gradolabs.com/

I found that in the $100-$300 range, Grados are the clear choice. They're ugly as hell, but sound is amazing.

Re:Hard To Tell Difference

[Wavicle]

Then, you have to do a blind test with all of them. You also need to use a variety of source material, because different genres of music compress better under some encoders.

I don't disagree with you, but I just wanted to throw in my own 2 cents worth of informal experimentation:

I recently discovered the sourceforge cdex ripping software, so I finally had a chance to rip all my music to the superior sounding ogg format instead of mp3. Before doing so, my wife and I ran a couple double blind tests with one another to see where the best encoding was.

The only pair of speakers I had to test this was a pair of old Yamaha YST-M7's. These are Yamaha branded $20 single driver computer speakers that came with some computer I bought a while ago. They are pretty bad speakers. For the test, I selected a reasonable genre swath of music:

Dixie Chicks "There's your Trouble"
Oingo Boingo "On the Outside"
Samuel Barber "Adagio for Strings"
W. A. Mozart "Queen of the Night's Vengeance Aria"
REM "Nightswimming"

Each piece was selected because of particular aspects of song such as use of strings, use of horns, or use of voice. Each song was tried in a variety of encodings in both ogg and mp3, constant and variable bit rate, with the original CD wav file thrown in amongst the samples. The mp3 encoder was Lame v 1.27 engine 3.92 Alpha 1 MMX, the ogg encoder was Ogg Vorbis DLL Encoder v 1.09 enging 1.05.

The results strongly disagreed with conventional wisdom. In every case, across genres, on these low end speakers, 320Kbps mp3's were the only ones that fooled our ears. Low bit rate ogg and mp3 recordings were different, but we didn't take time to notice which was better... they were both unquestionably inferior to the source material. Ogg's 350Kbps encoding was good, but inferior to the smaller 320Kbps mp3 files of the same work.

Reading some of the posts on this article, I am rather shocked how many people find sound reproduction to be anywhere between "very good" and "excellent" on mid end equipment listening to 192Kbps encoded audio.

After running this experiment, I ripped about 30 of my CDs to 320Kbps mp3's and noticed another benefit to CD quality rips: I could listen to the music longer without my ears feeling fatigued. I had always thought that it was pumping sound directly into my head from my headphones that caused my ears to become tired of the music. For whatever reason, it takes much longer now. Perhaps 3 or 4 hours compared to 1 to 1 1/2 before.

Re:Hard To Tell Difference

[evilviper]

So what exactly is your argument?

First of all, this claim is refuted by every test ever done:

In every case, across genres, on these low end speakers, 320Kbps mp3's were the only ones that fooled our ears. Low bit rate ogg and mp3 recordings were different, but we didn't take time to notice which was better... they were both unquestionably inferior to the source material. Ogg's 350Kbps encoding was good, but inferior to the smaller 320Kbps mp3 files of the same work.

If you honestly believe it, it's either because you simply like the sound of MP3 distortion, or you really wanted to like MP3, so you've conviced yourself that you do. Personally, I just assumed you were trolling because of your following comments:

I ripped about 30 of my CDs to 320Kbps mp3's and noticed another benefit to CD quality rips: I could listen to the music longer without my ears feeling fatigued.

That is just plain bullshit. No audio codec is going to relieve fatigue. Even if you do believe it.

Working with people, I have discovered that people convince themselves of many things. When something happens to their computer that they don't understand, they grasp onto the last thing that they did understand. This is very clear when you see cases of people claiming a change they made to the BIOS make their computer stop booting, when it was actually just a computer virus infection. People who are convinced that moving their computer to another room made it run much slower, but they moved it around the same time that they upgraded from Windows 95 to 98. Etc. If really feel less fatigue, I can only assure you it has nothing to do with the lossy codec you are using.

To be fair...

[Gropo]

Don't forget that Apple's AAC's aren't ripped from 48.8 16-bit AIFF's, but re-mastered directly to AAC.

Re:To be fair...

[Gropo]

How do you know it's ADAT rather than analog 1"? Probably is ADAT in alot of cases, but nevertheless, I recall Jobs' statement (for whatever it's worth) in which he claimed: (paraphrased) "Sometimes they sound better than CD's themselves"

Re:To be fair...

[verloren]

Ripping from the source isn't necessarily an advantage. Much (if not all) of the work on such codecs is done to optimize them for ripping from CD or movie soundtrack sources. Something with more information than that (which presumably is the good thing about doing it direct from sources) is supplying a load of information that, at best, the encoder would discard anyway, and at worst might actually confuse it.

Cheers, Paul

Re:To be fair...

[Jeremy Erwin]

CD-DA isn't AIFF. CD-DA contains either 2 or four channels of 16 bit audio, sampled at 44.1 kHz, organized into blocks of 2352 bytes. It's big endian (unlike *.wav).
AIFF is a rather more involved format. One of those formats is 16 bit, 44.1 KHz audio.
The only benefit I could see to encoding directly from masters is that it is possible that the "master" could be less prone to jitter. It is concievable that higher resloution masters would be available (96Khz/24 bit) and the encoding process could take advantage of this extra data somehow.

That's all very well but

[Sad Loser]

Some decent quality properly blinded listening tests would be more interesting than a graph though.
When VHS established dominance of the video market, there were high barriers to change - your player and media were committed to that format.
There are far less barriers to change in the ripped audio format, although there will still be some inertia, but there is nothing* to stop ogg vorbis becoming the dominant format.

Where's my ogg pod then?

* apart from the silly name.

Re:That's all very well but

[jc42]

A few years back, Consumer Reports did an interesting set of listening tests. The usual blinds, of course. But the interesting part was that in addition to random staffers, they had two extra groups: sound engineers and musicians. They reported that these two groups differed radically in their rankings of sound quality. The difference was fairly straightforward: The sound engineers gave a high rank to equipment that produced the sound accurately. The musicians gave a high rank to equipment that made the music clear. These are not at all the same thing. In particular, musicians generally liked "distortions" that removed non-musical information, strengthened the fundamentals, and so on.

From a musician's viewpoint, one of the real frustrations with just about anything published about sound quality is that it's always written from the engineer's viewpoint. But what I want to know is which gadgets do a good job of reproducing the music. They never seem to tell you that.

Re:That's all very well but

[The Original Yama]

A decent, but simplistic article. Unless you're a fussy audiophile, this analysis should be sufficient for you.

[rant] I wish the author would present his graphs in a more readable way. A screen dump of Photoshop in WinXP is not a professional way to show data. It's ironic that while reviewing lossy audio formats he opts to use a lossy image format (JPEG) for the graphs. I had to double their size on my screen just to make some sense out of them. [/rant]

It's not difficult to gain better-than-CD quality. CDs have been around since the early 1980s, and their main drawback is that they have a low sample rate, 44.1KHz. This is why many sound engineers prefer vinyl. because it's an analogue format, vinyl has a potentially infinite sample frequency range (although it's obviously limited by the recording and playback equipment, and by the physics of the media itself). Apple has used original masters (not CDs) to create much of its song library, so all they have to do is encode at a higher frequency than 44.1KHz. At a guess, they're probably using 48KHz, which is on par with DAT and MiniDisc.

I'm not surprised that Apple is using AAC. For one thing, it is clearly better than the decade-old MP3 format in all respects, and the licensing costs are probably the same or better. Technically, it may not be as good as Ogg, but most people don't even know what Ogg is so it doesn't matter. As long as Apple can say "our format is better than MP3 and CD audio" (the two prevailing formats), they will have the attention of consumers. AAC is a more mature format than Ogg (Ogg isn't bad, but AAC is more tried-and-proven), and is probably more compatible with existing DRM technologies. DRM is important to keep the recording companies happy and to ensure that the files will only play on devices that Apple specifies (like on Macs and iPods).

A major stumbling block for Ogg is that until fairly recently it was necessary to use a floating point processor to play the format. In the arena of portable devices, only PDAs have floating point capability, which is why you can play Ogg files on your Zaurus and not on your iPod. AAC is already supported by many devices, so Apple has a larger potential market (although at present only iPods can play the files).

Re:That's all very well but

[norton_I]

If the musicians like it that way, they should record it that way. Sound reproduction equipment should do just that -- reproduce as accurately as possible the sound on the CD (or other source)

If people deliberately want to alter the sound, that should be done by effect processing that can be turned off, but not built in by inherent limitations in the reproduction equipment.

Now, if you are interested in sound production, that is another matter entirely. The sound of a (say) guitar amplifier is as much a part of the musician's instrument as the guitar, though it would still be nice if a lot of that load could be taken off of unreliable power amplifiers and placed on reproducable, removable low level effects processing.

Re:That's all very well but

[kcurrie]

A major stumbling block for Ogg is that until fairly recently it was necessary to use a floating point processor to play the format. In the arena of portable devices, only PDAs have floating point capability, which is why you can play Ogg files on your Zaurus and not on your iPod. AAC is already supported by many devices, so Apple has a larger potential market (although at present only iPods can play the files).

Actually the Zaurus DOESN'T have any floating point either, the ogg player is all integer. Details can be found in this ZDNet story.

Re:That's all very well but

[jc42]

musicians are legendary for listening on poor equipment and filling in the rest of the music mentally

Yes, of course, but there's a different interpretation of this. It's not unusual for musicians to intentionally use low-quality equipment in order to make the music clearer. They aren't overcoming the limitations of the poor equipment; they are using it as a tool.

As an extreme example, I've known a number of musicians who have recordings of harpsichord music, but don't like the instrument itself. The reason is simple: They have good high-frequency hearing, and a live harpsichord is just a loud high-pitched buzz with barely-audible music in the background. But with a recording, especially on low-quality playback equipment, you can wipe out the high frequencies. This makes the music audible.

There are a fair number of people who have a similar reaction to violins. Although it's not as bad as a harpsichord, a violin has strong high-frequency harmonics that are often badly out of tune. If you clip off everything above 15 kHz or so, you eliminate this distracting noise and the music comes through.

I've made a lot of "very live" recordings of dance bands with a room full of dancers. One of the tricks that I've learned is to use fairly cheap mikes that don't hear the low or high frequencies. Then I don't have to do as much processing to get a good sound.

An interesting thing about this: I've occasionally made two recordings, one with good mikes and one with poor mikes that fall off around 12 or 14 kHz. When I play them for listeners who were there, they inevitably say that the "poor" recording sounds more live than the "good" one. What seems to be going on is that the human brain is fairly good at compensating for the low- and high-frequency noise in such situations. Participants don't hear all the background noise. But in a quiet room with the noise coming from a speaker, people do hear it.

This is similar to the phenomenon that photographers will tell you about: The human eye/brain system is very good at correcting for color cast. Cameras record the true color (within the bounds of the film type and latitude), so the cast is visible in the photo when it wasn't in the original scene. But photographers learn to see the full color and can't ignore a color cast, just a musicians learn to hear all the sound and can't easily ignore background noise.

(Similarly, after playing around with a polarizing filter for a few months, I found that I could "see" polarization. And now I can't turn it off. ;-)

It's all very complicted.

Re:That's all very well but

[CharlieO]

This is similar to the phenomenon that photographers will tell you about: The human eye/brain system is very good at correcting for color cast. Cameras record the true color (within the bounds of the film type and latitude), so the cast is visible in the photo when it wasn't in the original scene. But photographers learn to see the full color and can't ignore a color cast, just a musicians learn to hear all the sound and can't easily ignore background noise

Well this photographer will tell you differently.

If you use film stock then a very important part of the printing process is setting the filters to give the correct colour balance - either by hand or by bulk scanning the film and normalizing to 18% grey.

On a digital camera or video camera you have to set the white balance so the camera electronics know the reference to record the colour signal against.

Neither film nor CCDs/CMOS sensors have anywhere near the dynamic range of the human eye, so they record a substantially less accurate picture with either the highlights or shadows saturated out.

The only way of accurately scientifically measuring the scene is with a multispectral scanning radiometer - as used in remote sensing.

Speaking as a sound engineer I find it difficult to agree with your stance about this odd entity 'the music' - every stage of the process should be as flat as possible unless it is an artistic decision to change it. So if I'm recording a live event I should use the best mics, with the flatest response, use the recording device with the flatest response on most headroom, and then master the recording. Now at this stage I can play around with the EQ on the recording and make an artistic decision on the timbre and tone of the sound - because I have not predisposed myself one way or the other by colouring the sound I recorded. I don't disagree that a doctored sound might sound better, but it is not more accurate.

In the real world systems aren't perfect, and those that are close cost a lot of money. Now you have to make a decision of what makes the best sense with your budget. Now some mics and recording systems colour the sound in a pleasing and predicateble way - it sounds like the setup you settled on does. A lot of people forget that the post production of a recording or the setup of the PA at live gigs is a very important part of the music creation process, guitars drums and keyboards may be your instruments of choice, but for a sound engineer the instruments of choice are mics gates EQs compressors and sound desks - in producing a recorded work both the musicians and engineers are important - would the Beatles work have been the same if it hadn't been for the creativity of the Abbey Road engineers who broke from the tradition of 'perfect reproduction' and started working with the musicians to create new ways of presenting the sound - probably not.

In your example the rolloff at high frequency is a common effect with high volume PAs - at high SPLs your ears get tired and the high frequencies are affected first. Most people can relate to that slightly muted feeling to thier hearing after a particularly good gig - so the slightly muted nature of the mic that you use matches people recollection of live gigs. Interestingly popular mics for live work will not be the same as those for live work - even with the same instrument and musical style.

Re:That's all very well but

[fataugie]

musicians are legendary for listening on poor equipment and filling in the rest of the music mentally.

THank you, you just explained Bob Dylan to me. I knew there had to be something I was missing....

Re:That's all very well but

[smilinggoat]

Apple has used original masters (not CDs) to create much of its song library, so all they have to do is encode at a higher frequency than 44.1KHz. At a guess, they're probably using 48KHz...

Even if they are using 48kHz sample rate, they're still compressing the hell out of it, which destroys all those extra frequencies you're getting over 44.1kHz (22.05kHz - 24kHz). AAC does the same thing MP3 and vorbis does, which is chop off a significant amount of high frequencies to cut down on data.

And besides, the original masters could have been tracked at 44.1kHz, 16-bit in ProTools or what have you. Not necessarily any higher than that.

Re:That's all very well but

[firewood]

A major stumbling block for Ogg is that until fairly recently it was necessary to use a floating point processor to play the format. In the arena of portable devices, only PDAs have floating point capability, which is why you can play Ogg files on your Zaurus and not on your iPod.

Palm OS 5 PDAs (Zire 71, Tungsten T) only have integer ARM CPU's, and they play Ogg files just fine (running AeroPlayer or PocketTunes). And the Apple iPod uses a very similar ARM CPU core.

Re:That's all very well but

[jc42]

Cool. So you can see polarized-type 3-D movies in 3-D without wearing the special glasses? :)

Heh; no. It doesn't seem to work that way, at least for me. I seem to know without thinking about it whether light is polarized, but I can't actually tell what the polarization is. If I think about it, I can, but that's from experience.

Zoologists have reported that some animals can detect the direction of polarization. One of them is the common pigeon. The doves apparently have a polarizing filter inside their eyes.

This was reported by people studying pigeons' direction finding, which they are notoriously good at. One thing was discovered was that they weren't as good on overcast days as on sunny days. They got good evidence that the birds used the sun's position and the time of day as a compass. Then they found that if there were a couple of spots of blue sky visible, the birds apparently knew where the sun was, even if it was hidden behind clouds. The explanation is that blue sky is polarized, and the polarization points away from (or towards) the sun. It's strongest 90 degrees from the sun, and weaker near the sun or near the horizon. So one patch of blue will give a pigeon a line that the sun lies on; two blue patches tell them where the sun is.

These birds also seem to be able to detect the planet's magnetic field, giving them a second compass (which has failure modes near some sorts of human artifacts). Lots of critters, including a lot of bacteria, have a magnetic sense based on tiny crystals of magnetite. We apparently don't have any magnetite in our heads. But I wouldn't be surprised to read about a weak magnetic sense in some humans. Who would have thought that the human eye could detect polarization?

Get yourself a polarizing filter and experiment with it. It's fun, and after a while, you'll find yourself knowing what it will do to a scene without thinking about it. You'll somehow know that some surfaces (and skies) are sending polarized light, and you'll know when you want to cancel or enhance the polarization with your filter.

I haven't read that the mechanism is known in humans. It's possible that the human eye really can't see the polarization. Rather, your brain might "just know" what surfaces produce polarization without any conscious thought.

Spectrum analysis is useless

[Anonymous Coward]

Really, these codecs are supposed to change the waveform and spectral content. They are lossy!

The only thing that counts is if they remove the right stuff and keep the stuff we like to hear. Only listening tests are valid to judge a lossy audio codec!

Re:Spectrum analysis is useless

[Jon Abbott]

According to this blind listening test conducted by c't magazine, AAC at 128kbps was ranked the lowest of all codecs sampled at that bitrate (WAV, OGG, WMA, RA, MP3Pro and MP3)... One can always hope that the claims of Apple making their AACs directly from the record masters are true, as this would help the situation some.

Re:Spectrum analysis is useless

[MS_is_the_best]

How can this parent be +5 insightful? It is wrong and uninformative.

I worked with MPEG4 (AAC) and OGG a lot (for my phd. thesis) and spectral analysis IS very important. Although it is correct that it doesn't show precisely what information is left out because of what our hearing system doesn't register. However, these hearing curves and integration times are already known (although not the same for evry human) and most post-MP3 encoders do this rather correct. Most profit nowadays is in clever signal processing. The spectrum of a decoded signal shows almost all artifacts very well and is therefore something which helps a lot in showing artifacts in a coding scheme.

Of course listening test must also be done. They show that modern encoders make choices (not all our ears are the same, and so isn't all the music) which very often pays of in a certain test.

Theoratically AAC and OGG are rather similar, but AAC has a few nice extra's like the Temporal Noise Shaper. However in practice OGG seems good enough (unless MP3) and is free, while AAC is not that much better and unfree, so my choice is obvious.

I will wait for the OGG hack of the IPod, now it had a better processor.

They chose AAC because it's already in QuickTime

[Fefe]

And it's more efficient than MP3.

Their encoder is not particularly good, and AAC is covered by a ton of patents, so there probably are other reasons why they chose it.

For anyone else but Apple I see no reason to use AAC when you can have Ogg Vorbis.

PS: Shameless plug: I wrote a vorbis patch to add SSE support for enhanced encoder and decoder speed. It also contains some 3dnow! optimization for you K6 users, decoder only.

PhatAudio is on Ogg's dick

[ObviousGuy]

Nothing will every beat Ogg in PhatAudio's eyes. They seem to find evidence of Ogg's superiority where there is none. It's like the lovers of vacuum tubes rather than transistors.

"It sounds warmer!"

Sure. And the incandescent lights in my house have a better smell than the fluorescent ones at work.

Re:PhatAudio is on Ogg's dick

[rm -rf /etc/*]

Tubes and transistors are different though. With Ogg vs whatever, it may be more subjective, who knows. But at least with tubes there is a known difference between how they amplify and how transistors amplify. Tubes produce more even order distortion, which to our ears sounds warm and pleasing. Transistors produce more odd order distortion, which tends to sound harsh and stressing.

Subtle difference? Perhaps, but it's there.

Re:PhatAudio is on Ogg's dick

[afidel]

Umm, no there is a big difference, solid state amps reproduce sounds more exactly but can introduce harsh harmonics, on the other hand tube amps tend to add warm harmonics while distorting. These warm distortions are more pleasing to the ear, of course ideally you would produce zero distortion and get your harmonics from an effects processor =)

Re:PhatAudio is on Ogg's dick

[norton_I]

This is somewhat true(*) with hi-fi gear which is not generally run anywhere near clipping limits. In that case, both valve and transistor amplifiers operate as nearly ideal amplifiers, and sound is very similar. However, sound production gear, particularly guitar amplifiers are almost always run outside of the linear range, where the characteristics of individual amplifiers become significant. This is because if you had to listen to the flat lifeless sound of your average electric guitar without the harmonics added by an amplifier, you would go nuts (no comments about going nuts either way are necessary here).

I have measured output of some tube amplifiers, and you can easily hear the difference in a simple sine wave signal, which show up easily by looking at the waveforms or power spectra.

Also, when distorting, there is far more than the "even/odd harmonics" theory affecting the relative sounds of different amplifiers.

(*) There are still real differences. Valve amplifiers typically have output impedances of a couple ohms, while transistor amplifiers usually have nearly 0 output impedance. This makes a big difference in damping, which contributes to what audiophiles people call "warm" vs. "tight" in a way that depends heavily on the speaker driver and enclosure. Valves also have inherently higher THD figures than transistors (commonly .2% vs .001%), and several "old school" valve amplifiers run without negative feedback in which case they are never even approximately linear, and do not behave as an ideal amplifier at all.

Hmmm

[akpcep]

What about if I tell someone I'm off to trade some OGGs with my friends, and they think I'm going to throw little plastic discs about?

Maybe in the future...

[borgdows]

"the increasingly popular OGG codec."

sadly, I don't think OGG is *currently* known to anybody except nerds or IT pros.

Re:Maybe in the future...

[FearUncertaintyDoubt]

"sadly, I don't think OGG is *currently* known to anybody except nerds or IT pros"

Entering geek-fantasy bizarro world, please wait...

Marketing department hottie: Oh you sexy IT guy! Tell me more how I can get higher quality and higher compression rates on my music files! I want to know ev-ery-thiiinnggg!

Meanwhile, back in reality...

Marketing department hottie: [silence as she passes by, avoiding piercing leer of geek]

Geek: Hmm, I wonder if she noticed me. Doesn't she know the powers of music compression that I possess? (note to reader: she didn't, and she doesn't care)

Re:Maybe in the future...

[CraigoFL]

When you start at zero, anything more than that is "increasingly" :-P

Re:Maybe in the future...

[Azghoul]

You're right. We should just give up, and use whatever the "winning" format is. We should all by Toyota Camrys and Honda Accords, we should all just vote for one of the two major parties, etc. etc. etc. Heck, those Newtonion physics were pretty much good enough and the average user didn't need anything better...

What does "the average user" matter? Innovation seeks to push the boundaries, not cater to the masses.

Mirrors

[brejc8]

Does anyone want to add a mirror of the comparison?

/. effect strikes again

[Jon Abbott]

Spectrum analysis was used to see which format did the best job of maintaining the shape of the original waveform.

Furthermore, "ping analysis" was used to see if the webserver survived the /. effect, and tests conclusively show that this is not the case. :^)

Ogg

[91degrees]

Most people who use ogg do not use it for it's quality. All that matters in that respect is that Ogg is comaprable to other formats at similar bitrates.

The important aspect of it is that it's free. There are no patents (at least as far as we know of) preventing anyone from using it, and it's made quite clear that the code can be included in open and closed source software without royalty payments.

Re:Ogg

[Agent Green]

Well, I switched because of it's better quality, particularly in the low bitrate arena for lectures...and for all my CDs. Yes...I re-ripped everything I owned once I got a taste for the format.

Using a Winamp vorbis encoder plugin, I was able to achieve significant crunches on classroom lectures, that were close enough to the original to be useful. Bear in mind too, that this was before Speex became part of the project.

MP3 on the otherhand was totally useless at anything less than 64k. The loss drove me nuts.

Let's not consider only that Vorbis is free...but it's also further extensible. Last I knew, none of the "new" audio formats being touted could support up to 255 discreet audio channels...which could be a very big hit with multispeaker surround systems well into the future. Bitrate peeling promises to be very exciting...once the details of that are all worked out. The Ogg multimedia foundation will be a true thing of beauty.

And it's free not just from the licensing and patents...but also from that DRM BS that all of us hate so much. Probably another reason Apple decided to go with ACC was to get the DRM support from the record labels.

Re:Ogg

[91degrees]

And there are no patents preventing anyone from using MP3,

Tell that to the guys that received this letter

Unfortunately I'm sticking with MP3

[jolyonr]

I agree that Ogg is a better format, better quality sound for similar bitrates to MP3, but until the portable devices I use, in-car CD/MP3 players, etc. accept the Ogg format as readily as they do MP3, then I (like most people) are stuck with the MP3 format. At least nowdays storage is cheap, so I whack everything to MP3 at a high bitrate.

Re:Unfortunately I'm sticking with MP3

[Thanatiel]

I do it the other way.

I do not buy a portable player which does not supports Ogg.

Re:Unfortunately I'm sticking with MP3

[Carrot007]

The only sane option, and one which is becoming increasingly viable (cost / storage etc) is having a pda, pda's will run any software by their nature and there are now able to provide enough power and storage to become your portable music player, all you then need is a line in on your car radio and your happy.

And them you can play all your music whatever the format! (remeber a lot of "players" put restrictions on bitrate / vbr)

Re:Unfortunately I'm sticking with MP3

[jolyonr]

Now, of course, if I lost my wife down the back of the sofa then I'd be able to go out and get a new Ogg-playing device without being shouted at!

Re:Lossless

[the_bahua]

Nevertheless, I encode into flac now, as 1) it sounds much better than vbr mp3 or ogg, and 2) at 20-30MB per song, it really discourages people from downloading songs from me when I tell them how big they are.

pretty lame!

[bromoseltzer]

This is not much of a comparison. Spectrum analysis is not enough to tell you what a musical track sounds like. Kinds of distortion that sp. analysis may not pick up: harmonic (e.g., from clipping of high levels or quantization of low levels), transient (percussion, attack), intermodulation (tones "beating" against each other), dynamic range (noise at low levels vs maximum loudness), phase (relationship of pure signals at different frequencies), and on and on.

So it's interesting to compare the Apple codec with all the others, but this review doesn't do it.

-mse

Re:pretty lame!

[trezor]

And as all people who have taken advanced math knows: Sound can be described with equal precision in the time-domain and in the frequency-domain.

It's called a Fourier-transform.

And in the frequency-domain you still got phase, in case you wondered. It's covered by the use of imaginary-numbers.

So analysing the signal in the frequency-domain should uncover the same errors as an analysis in the time-domain, if it's extensive enough, that is.

I don't bother going into the theorys behind this, but google for Fourier-transforms and wise up :)

Re:pretty lame!

[trezor]

And as you surely know: FFT stands for Fast Fourier Transform and is one special implementation which is not a complete Fourier Transform. I'll not go into boring details here, as you seem informed enough :)

As I know little specific about MDCT I will not go out on a troll raid either, but it's still a Cosine-based transform. Hence a Fourier-derivate work.

So my point still stands. Given a proper transform (I never mentioned FFT), you will keep phase information even in the frequency-domain, and a frequency-domain analysis will not be inferiour to a time-domain based analysis.

Re:pretty lame!

[glwtta]

It's covered by the use of imaginary-numbers.

Yeah, I noticed that a lot of reviews of this type use imaginary numbers.

It's Vorbis, not Ogg.

[Anonymous Coward]

Ogg is a container format. I could in theory put an ACC audio file into an Ogg container.

The audio format you're babbling about is Vorbis. Usually .ogg because it is inside an Ogg container.

Hell, it's not just a silly name problem, it's an entire naming convention issue.

Re:It's Vorbis, not Ogg.

[repetty]

"Yeah, and the correct term for .mp3 files would be MPEG Layer 3. But it isn't so."

Please go back and read his post before you reply.

His point is that .ogg is a container like Apple's QuickTime is a container. If you listen to a QuickTime sound file you might actually be listening to a file encoded in mp3 or Vorbis, or a half-dozen other codecs.

Get it?

Anyone seen real specs for Apple's format?

[tgd]

I spent some time last night playing around with the new Music Store feature in iTunes 4. Besides the fact that iTunes crashed on me twice, and 3 never crashed on me, it seems like a very well put together feature.

What kept me from buying the dozen or so tracks I found that I thought were worth a buck a pop was the fact that my Rio Receivers need MP3 or, via "upgraded" software, FLAC, etc... Although the AAC->CD->MP3 route is possible, and I intended to buy a track and see how the quality comes out, has anyone seen anything about how the DRM works on the Apple files?

I'm wondering if there are any libraries out there for decoding them, even within the confines of the DRM... just so I can get them into either a raw data stream or something so I can play them on my Rio Receivers... I'd probably switch to buying all my music (where possible) from them, if thats the case... but if I can't get them into a format I can play using my existing equipment, I'll have to pay the five buck "CD"-tax to get them in a format I can rip to high-bitrate MP3.

Re:Anyone seen real specs for Apple's format?

[s.o.terica]

Although the AAC->CD->MP3 route is possible, and I intended to buy a track and see how the quality comes out, has anyone seen anything about how the DRM works on the Apple files?

Regarding the AAC->CD->MP3, I burned a couple of Music Store tracks to CD, then re-ripped them (using iTunes, no less) using VBR High, and they sounded indistinguishable from the original Music Store files (albeit being significantly higher average bitrates).

Regarding DRM, it appears that your Music Store file is locked to your Apple ID, and you have to Register up to three computers that you want to be able to play songs associated with your Apple ID. If you sell a computer, you have to unregister it before you can register a replacement computer. This appears to be the only restriction on usage -- you can still burn the songs to as many CDs as you want, copy them to as many iPods as you want, and streamthem to as many other Macs (and TiVo) as you want using Rendezvous.

Re:Anyone seen real specs for Apple's format?

[Zathrus]

Note that you cannot stream AAC's directly to TiVo -- there is no support (and I doubt support will be forthcoming). You'd have to re-rip them to MP3 first or do it on the fly - TiVo can only play MP3's natively since that's what's supported on the MPEG decoder.

I suppose that someone will get around to writing a wrapper to do this on Macs... it's a shame that TiVo didn't just release the source to the TiVoServer (for both Windows and Mac) so people could just hack support into it directly.

Re:Anyone seen real specs for Apple's format?

[MasterVidBoi]

I'm wondering if there are any libraries out there for decoding them, even within the confines of the DRM...

While I'm not sure, I would say yes.

I noticed last night that the protected AAC files played both in the Finder's preview pane and in Quicktime 6.2 itself. I assume the actual AAC-Protected decoding is done in quicktime, and no modifications were made to the finder to allow it to explicitly play AAC-Protected files. This implies that any program that can use quicktime can also play protected AAC files.

I'd be suprised if may of the other mp3 players on the mac didn't already support playing via Quicktime, and by extension, playing AAC-Protected

Re:Anyone seen real specs for Apple's format?

[dschuetz]

I burned a couple of Music Store tracks to CD, then re-ripped them

A coworker recorded a few songs to CD last night. This morning, I ripped them to q7 Ogg Vorbis, and downconverted those Ogg files to MP3 (VBR, 160 to 256 kbps).

Listening to them (on decent speakers, but still computer speakers nonetheless, and also through headphones), they all sound pretty good. I'm listening mostly for "bad artifacts" -- pumping, popping, clicking, phasing/flanging, stereo movement, etc. I can't hear anything of the sort, even on the MP3.

So, we've got WAV -> 128 AAC -> q7 Ogg -> 160+ MP3, and it's still quite listenable. Certainly, it's not studio quality, but for listening at home, on a typical system with typical speakers, it's pretty good, to my ears.

I'm still sort of annoyed, philosophically, at not being able to get a full-bandwidth .WAV file. I mean, you're paying for the track, you should get the exact same data as you can when you purchase the CD outright. But as a "best of evils," this is very good. And, truthfully, I'm not convinced that other similar services (like Listen.com's Rhapsody) don't do essentially the same thing.

Can anyone suggest a good 'test pattern' file? Something with lots of dynamic range, easy-to-identify instruments (especially with lots of layers of detail), variations in note types / waveforms, etc.? Basically, an Indian Head for audio. Because it'd be great to be able to say "download this .wav, and as you decrease the bitrate listen for the flutes at 0:35 to start sounding weird" or somesuch. Just a thought.

Anyway, I'm satisfied with the quality, at least on the minimal sample set I've heard.

Re:Anyone seen real specs for Apple's format?

[illumin8]

Wow, that is a lot of decompression and recompression going on in your process. I know the difference might not be audible to you, but you should really reconsider your process. Every time you use a lossy compression scheme you are losing more and more data. Each compression algorithm has to compromise in some way and by using so many different types of compression (AAC to OGG to MP3), you are getting the disadvantages of all three algorithms combined in your output file.

If I were you I would just stick with one format change if possible. Go from AAC to OGG or AAC to MP3.

But what does it actually sound like???

[velouria]

I don't think graphs are all that useful for comparing lossy sound compression.

Microsoft likes to show how their wma looks better than the other compression methods... it does look beautiful in graphs, but it sounds all tinny and horrible.

I don't care if the compressed frequency response graph looks nothing like the original frequency graph, as long as my ears are unable to tell the difference between the two.

Arggghh!

[Anonymous Coward]

Will people please stop talking about Ogg as though it were an audio compression scheme. It is not - it is a wrapper format.

I don't care what kind of tests were done, but anything comparing Ogg to a lossy compression scheme is bound to be unfair, as the Ogg family includes a lossless encoding scheme. Not only does Ogg include FLAC and Vorbis, but it also includes Speex, targetted at voice, and Theora, a video codec.

So please, stop trying to compare Ogg to MP3. It's like comparing AVI or Quicktime to MP3.

Re:Arggghh!

[Anonymous Coward]

Don't be a twat. Especially, don't be a pedantic twat. You know full well that when someone refers to "Ogg" they are usually refering to the Vorbis coded. When they want to talk about FLAC, Speex or Theora they say FLAC, Speex or Theora. So the names have become confused. Tough noogies.

Re:Arggghh!

[SophtwareSlump]

I think the Ogg people should change the file extenstion of Vorbis files to .VBS! Oh wait....

Re:Arggghh!

[bigpat]

Ogg is easier to say than Ogg Vorbis. Ogg is easier to write than Ogg Vorbis. Ogg is a lot catchier a name than Ogg Vorbis. It is very natural that Ogg Vorbis would be known as Ogg and that files would be known as ogg files.

No problem here, nothing to see, please move along.

Converting AAC (".m4p") to MP3?

[kriegsman]

My portable HD music jukebox, and my car stereo, and tons of other devices out there ONLY play MP3s.

But any new music I buy through Apple is AAC encoded, in an m4p "protected" file.

So here's a purely technical question: What's the shortest path to convert these shiny new "protected" ACC files into plain MP3s so that I can take the music that I've just paid for and listen to it on my Archos MP3 Jukebox? I've already successfully gone from AACs to audio CD, and then re-ripped and re-encoded the album as MP3 but ... ew. There's got to be a better way.

And yes, I know Apple and Big Music and the RIAA and Homeland Security don't want me to be able to do this (easily, or maybe at all) but at this point I'd like to sidestep the politics and focus on a technological solution that works for me- a legit, paying user.

So: what's the closest we can get to "acc2mp3", or better yet "m4p2mp3"?

-Mark

Poem.

[Anonymous Coward]

There once was a codec named Ogg,
It's name was peculiar and odd,
It replaced MP3,
Because it was free,
Hey, what the fuck is an Ogg?

Two Words

[Anonymous Coward]

Beta-Max!

Ogg = Too little, too late, overmatched and unknown to the masses. Also, too geeky. No hardware support to speak of. Walk down a street anywhere in the world and ask them what Ogg is, then ask them what MP3 is..... I guarantee you 1000 more people will know what a MP3 is compared to Ogg. It may be smaller, but in the age of 200 Gb harddrives for $200 size is no longer an issue.

MP3 = Widely known, was first on the scene, its everywhere, tons of hardware on the market, good quality, reasonable size ... hell my grandma even knows what it is.... that means Ogg is screwed!

AAC = Already has an installed user base, sounds just as good as Ogg or MP3, plays nicely with the best known\most widely sold MP3 player on the market. Promising, but probably the lesser of the three unless this thing takes off.

You may not like what I have to say, but it is the truth.... and you all know it!

Re:Two Words

[Lxy]

Yes, until someone gets sue happy and starts suing MP3 and AAC users. Maybe it will happen, maybe it won't.

Look at GIF, JPEG, and PNG. GIF is used for its quality, JPEG is used for its size, PNG is used by geeks. Unisys started suing webmasters, now the patent holder for JPEG is ruffling feathers, PNG is slowly becoming the accepted format. All it takes is some greedy SOB to make Ogg an attractive format.

Re:Two Words

[Knobby]

Can you point out one player? Because I've never seen them.

Yep. The 5GB iPod I bought over a year ago plays AAC encoded files (after installing the v1.3 Firmware Update), as do the other 700,000 iPods out there. Combine that with the new Apple music store, and overnight you've got a whole lot of AAC encoded music out there with hardware support.

Re:Two Words

[otis wildflower]

Yeah right. AAC support on MP3 players? Since when? Can you point out one player?

As a matter of fact, I can.

Re:Two Words

[vadim_t]

PNG can also store true color images, while GIF is limited to 256 colors. If you have a picture with many colors and things like lines or text then PNG is the only thing that will work well. JPG will mess the text and thin lines, GIF will remove colors.

Re:Two Words

[danwatt]

TIFF is a wrapper format (more or less). By default it is lossless-uncompressed, but there is also a lossless-compressed format (I think using deflate or LZW or similar), and some (Adobe) have even extended it to support JPEG (JPEG inside a TIFF file....) and ZIP (zipped photo data inside a TIFF file).

See the similar argument for ogg being a wapper format : OGG supports Vorbis (audio), Theora (video), Speex (speech audio), and FLAC (lossless audio, though I don't think its 100% integrated just yet).

The only problem with Ogg

[falsified]

My personal experience with Ogg is that it takes forever to rip a CD using the format. I personally don't know why this is (perhaps just a problem with the software I was using?) but if it's going to take 20 minutes to rip three tracks on a 48x CD-ROM drive connected to a 1.8 (don't laugh, it's fast enough for piracy!) gig processor, then I might as well just rip to mp3 at 192 kbps. Storage is cheap as hell nowadays, and most people (myself included) don't need 40 gigs on their hard drive but somehow ended up with it.

Re:The only problem with Ogg

[BigBir3d]

If you use grip on linux, there have been very nice speed increases in the last year. My slow ass 24x cd-rom in my P3 500MHz Thinkpad will rip at 1.9x and encode at the same time at 1.4-1.6x

Re:The only problem with Ogg

[grolim13]

I'm guessing there's something wrong with your software set-up, as my poor 800MHz Duron can rip+encode at around 4x real-time.

As for not needing larger hard drives... well, I have a 60 gig which is about half full; it feels rather constraining at times - capturing video in full PAL resolution sucks up close to 1GB/min, and my CPU is nowhere near fast enough to encode that in real time.

About audio compression, CD-MP3 guide

[Compact Dick]

Arguably the best resource for audio compression information can be found at Hydrogen Audio. Visit the various forums, check out the excellent Foobar2000 win32 multiformat audio player, and learn.

I have also written a guide on ripping high-quality MP3s using CDex, aimed towards beginners. If you know people who use Musicmatch, help them switch to a decent, easy-to-use CD ripper.

Cheers,
CD

Anybody checked out Neuros?

[Ruri]

The Xiph folks have signed up to add Ogg support on the Neuros audio handheld. Its a firmware upgradable handheld which currently supports mp3, but will probably have Ogg support by mid-late summer.

Check out the highlights.

http://www.neurosaudio.com/

Re:Anybody checked out Neuros?

[Enry]

Neuros rocks. About the same cost as an ipod, but includes FM receive and FM broadcast that actually works.

Expansion is via backpacks, so as technology changes you only need to buy new backpacks instead of an entire new unit.

Re:I'm an audio analyst...

[shish]

Any explanation on *why* it's better? Better compression / algorhythms?

I've found that 64khz OGG (3MB) ~= 128khz WMP (3MB) ~= 128khz MP3 (4MB). Admittedly the WMP is *slightly* better, but I thought that's only because of the extra sampling rate...

Also for some reason when ripping from CD to ogg there's very little difference between 64khz and 128khz, but then 44khz is utterly unlistenable.

> If someone would like to come up with a different format that can actually compete, I'd be happen to lend you my expertise and objectively analyze it for you.

Why not just help improve ogg? Are there any major problems that would need a total rewrite to get past them?

bleat

[Gropo]

Well then that bolsters my original reaction, which is that regardless of the original source of these 'test samples', you'll be hard-pressed to lease the master and rip directly to .ogg or .mp3 like Apple has done with the AAC's available off their service.

an audiophiles $.02

[Anonymous Coward]

I you have a really good system (probably anything over 3k nowadays) then it is not worth it to use any lossless compression.
In my system we can hear the difference between mp3 320 and wav files. That said, the difference is small and you have to be listening critically... so

it comes down to cost. If compression is 10% worse, and you spent 5k on a system, then using compression costs you $500 of system quality. $500 at $.90 per gb for a hdd can give me plenty of capacity.

Also, with WAV I know I won't have to re-rip my music when the next new compression algorythm comes out.

Of course for a portable with anything but highquality headsets it is unlikely you could tell the difference between a good compression and lossless...

your ogg pod is here

[morcheeba]

You can get an ogg pod here. ok, it's a little rough, but it's getting better.

Musepack is better at the high-end

[Jack Comics]

MP3 this, OGG that, AAC somewhere in the middle... Sorry, I don't use any of the above. I encode all of my music into Musepack. At high bitrates, it's the best lossy audio codec, period. For more information on Musepack, see Case's Musepack Page</a>, or <a href="http://www.hydrogenaudio.org/index.php?act=S T&f=11&t=1927&">List of Recommended Musepack Settings</a>.

Musepack encoders and decoders are available for both Windows and Linux, with Winamp plugins available. The only real downside to Musepack is there is currently no hardware support. But having tried each of the codecs mentioned in this article as well as Musepack at the Quality 8 setting, Musepack is music to my ears each time.

MP3's dont have to mean low sound quality

[Anonymous Coward]

Mp3 doesn't have to mean lower audio quality. A lot of tests have been done by audiophiles and mp3's encoded correctly are indistinguishable from the wave files even for most audiophiles. In a lot of cases mp3's are better than ogg's as the LAME mp3 encoder has been tuned at high bitrates to ensure good audio quality while ogg format is only now being tuned at high quality settings. See hydrogenaudio for info on various codecs, chrismyden for info on how to create high quality mp3's and Ubershare for info on how to share your high quality mp3's, ogg's, MPC's with other people who only share high quality files. And until there are some descent harddisk players with ogg support most of us will keep trading mp3's because they are more useful. In the only real advantage that makes me want to use ogg's is the fact that they support gappless playback, which is still lacking in all the harddisk mp3 players.

An overlooked key point?

[prestidigital]

Understandably, most of the discussion here is about the pros & cons of various compression formats. But the first thing that jumped out at me when I clicked on the apple.com link was:

"Preview any song for free, when you find a song you want, buy it for just 99... It's what music lovers have been waiting for: a music store with Apple's legendary ease of use, offering a hassle-free way to preview, buy and download music online quickly and easily."

FINALLY, a business model for downloading music that makes sense! (Now if only I could afford to switch to Apple products.)

Next up...

[cygnus]

let's compare video codec image quality by streaming the data thru a hex editor in realtime. :)

I'm The Archangel Gabriel

[RobotRunAmok]

...and I gotta tell you, having played that trumpet and serving as Music Director for the Celestial Choir since the Dawn of Time, I know Audio, and MP3 is the way to go. I've analyzed OGG, WMV, AAC, and this cute l'il analog thing which that wack job Orpheus put together Back in the Day, and I must say, nothing beats MP3, in your or anyone else's universe.

Of course, I'm logging in here under a pseudonym, so you'll just have to trust me. But hey, would a member of the Heavenly Host lie to you?

Re:I'm an audio analyst...

[Anonymous Coward]

son, if you were an audio expert, you wouldn't be working for Real.

Re:Vorbis! Not Ogg, Vorbis!

[hesiod]

> Is it that difficult to grasp! Ogg is a container file! Vorbis is the audio codec!

IT DOESN'T F'ING MATTER!

Just like Linux isn't an OS, (it's a kernel) no one aside from you and some other geeks (not meant as an insult, I am a geek too, obviously) will ever convince others of the truth.
More importantly it doesn't even matter. The details are subtle and by continuing the geeky "I'm better than the stupid lusers" all you are doing is keeping Vorbis from becoming more popular -- people will become pissed off that they get hassled every time they mention it, and then ignore it in the future.

Re:They chose AAC because it's already in QuickTim

[ScooterComputer]

Two points:
1) Apple does not explicitly mention how their Music Store songs are encoded (neither what the source is nor what encoder they are using)---they very well could be using a higher quality AAC encoder than what ships with QuickTime, which has reviewed poorly. There exist, it should be noted, other professional level encoders that have reviewed much better.

2) That being said, Apple released QuickTime 6.2 at the same time as iTunes 4 yesterday, and one of the headlining new features is an enhanced AAC encoder. It is entirely possible that Apple has addressed problems with their encoder, and perhaps the new version would stack up better in blind listening tests.

Of course, it would have been nice if Apple could step out of the Reality Distortion Field for ten seconds, and do the "Right Thing". They had to have known that AAC--because of current, community-reviewed blind listening tests--would be a controversial choice. Why they didn't undertake/commission prior subjective testing and why they haven't bravely taken their encoder to the "street" and up against OGG and MP3Pro, I don't know...if they had, we wouldn't be arguing about how crappy their encoder was, we'd be arguing subjective listening differences. Now, this potentially great new service will suffer from a 3 to 6 month "shake out" in the more discriminating audiophile community (the people who recognize that CD is better than cassette, and can hear that 128 CBR MP3 is NOT CD quality) because of the technical merits of the quality of the encoder. No new service needs such hesitancy to overcome, much less one from Apple. I predict that the stigma of the quality demon is going to be a major adoption speed bump for this service among the group most important to its widespread adoption--the audiophiles.

Once again Apple (read Steve Jobs) makes the mistaken assumption that just because they SAY their stuff is better, everybody should just accept that--it is a clear misread of their (new) market demographic, which is proving to be growing more and more into a Slashdot crowd. If they keep ignoring the fact that their fastest growing fanbase is a fairly technical, information hungry group, they will certainly lose them as fast as they gained them...if there is one thing I have learned in my years of being a Slashdotter is that we are a fiercely loyal, but not easily fooled community, and we certainly don't suffer fools gladly.

Re:Bose??? Buahahaha

[MKalus]

Have you ever HEARD a good speakter????

Bose IS crap soundwise, they pumpt tons of bass into the sound in order to "fill the room" and drown out anything else.

The Cubes are pouplar with a lot of people because they are "neat" but there is only so much sound you can squeeze out of a small can. Turn the sub off on your Bose and tell me again how well it sounds.

Don't believe me? Go to a high end store in your area and listen to some speakers that cost the same as the Bose (and if you're "lucky" they sell Bose as well) and compare them. You'll be amazed, unless of course you belong to the group of people who think that all you need is bass.

I have a better plan

[JudgeFurious]

Last night I downloaded a bunch of tracks off of Apple's Music Store Service. I then played them (along with several tracks I already had in OGG and mp3) through my computers $9.95 speakers while holding my portable cassette recorder very, very close to the speaker (For the technical out there I was holding it close to the LEFT speaker and even turned the TV down some to get the best possible sound) and then replayed them all back on the same portable cassette recorder.

My conclusion is that all three sound like complete shit.

Re:Bose??? Buahahaha

[croddy]

No, sorry there Mr. A.C. -- Bose speakers are mediocre.

First, the subwoofer + satellite model is fundamentally flawed. 20Hz is directional. Bass doesn't "fill the room like fog" -- when a train's coming, you can hear the direction, right?

If you bought Bose, you overpaid for consumer grade stuff and the Circuit City man swindled you out of your money. Big 3-way cabinets produce a flat signal, but, granted, they take up space. Those tiny cubes sound like fluorescent lights -- almost white noise, not quite, but in a cheaper package. Sticking a subwoofer under the table doesn't make up for it.

If you want to listen to music, you should be prepared to make space for the equipment it takes to do it.

Re:I'm an audio analyst...

[Adrenochrome]

Why was this modded as flamebait?

WMA7 was a joke, sure, but WMA9 *is* very nice. Granted, you can't play it on anything but windows, but it sounds damn good even at 128kbps. I do need to spend more time with it on "tough" material (orchestral, opera, etc.).

I've also been playing with their latest video codec at HD resolutions, and frankly, it's wiping DIVX and XVID's butt at everything except encoding speed. Damn, they've actually done something almost right (the encoder app sucks, however).

Useless Comparison

[nathanh]

AAC/MP3/OGG are all based on psychoacoustic models. Comparing their decoded spectrums is pointless. The spectrum isn't supposed to be faithfully reproduced. Frequencies that your brain wouldn't fully hear aren't fully stored.

The only value I can see in a spectrum comparison would be to find obvious errors in the encoder or decoder. Like the 16kHz spike in the Xing encoder. But how likely is that going to be these days?

The only proper comparison involves a good hi-fi, a sensibly furnished room, and a comfortable chair. It is called "golden ear" testing and it's the ONLY way to compare psychoacoustic models.

Or at least it's the only way until the research scientists work out how the human brain works.

Re:Useless Comparison

[The Mainframe]

You're going to need a good sound tech, too. If you'd like to rent my golden ears, I'm available.

Re:The presentation...

[feldsteins]

My favorite part of this discussion is where slashdotters believe that they, the open source community and Ogg in particular are foremost in the minds of people like Steve Jobs as he unveils his new music service.

Get a clue already. Apple went with AAC because it's great quality, supports the (fairly mild and necessary to get the RIAA onboard) DRM restrictions for the service, and is a subset of the excellent MPEG4 video codec.

Even if Ogg is better quality at lower bitrate (a point that I am not convinced of, "waveform comparisons" notwithstanding), Apple has legitimate reasons for going AAC that have nothing to do with The Man trying to keep you and the open source community down. Jesus, it's not always about you, mkay?

Spectum analysis in invalid

[Compact Dick]

Learn why you shouldn't use spectral analysis to determine lossy codecs' quality.

The most respected technique is double-blind testing using an ABX tool such as PC ABX, WinABX or ABC/HR.

More info on conducting blind tests can be found at the PC ABX site.

OGG who?

[Frobozz0]

"and the increasingly popular OGG codec."

Amongst who? Slashdot readers? It's certainly not consumers. Everyone uses mp3 (mpeg 2 layer 3). Apple's AAC (mpeg 4) does sound amazing. I've bought several songs already in that format.

OGG may sound good, but I wouldn't know. It's going to be relegated to the nerd community (which I am a proud member), but I just don't see it breaking through.

Spectral analysis != psychoacoustic model...

[autopr0n]

Modern compressions schemes are supposed to make sound that sounds as much like the original as possible, not looks like the original on an FFT.

The only way to test this is to use double-blind listening tests. The spectral analysis stuff is absolutely useless for finding out how good the music actually sounds.

all 15 ogg listeners...

[Anonymous Coward]

all 15 ogg listeners are getting together to 'rally' at apple trying to get them to support ogg. they have each committed to buy at least 5 ipods each if ogg is implemented, so then apple would sell at least 15*5 ipods, and it will definately be worth the effort to port ogg to ipod.

fools. its a 'mass-market' device. no one in the mass market even knows what ogg is. (do you use ogg? yeah i like em over-easy.)

AAC is pretty weak, no marketing can change that.

[RoLi]

And it's more efficient than MP3

At low bitrates, AAC is very weak, at 128kbps it was the worst of all:

Study

I was one of the 3000 participants, btw. And my ranking which I gave (blind, I did not know which sample was which) confirms pretty much the results, at 64kbps, AAC was unbearable, while ogg was not distinguishable (by me anyway) to the original.

The only test where AAC didn't fail miserably was the "expert test" with only 8 listeners.

OGG has beaten all other codecs consitently at all bitrates.

CD is the problem, not wma, mp3 or ogg

[nxs212]

CDs have flat sound to begin with when compared to analog masters. So in order to get "better than CD" quality you would have to rip from the master tape. Also, file size would have to be less than 60mb per song. (size of a 5 minute uncompressed song from a CD)
While most master-to-CD transfers sound fine, classical music tends to lose its "warmth." I am no audiophile but I noticed a big difference when I listened to Crux Shadows live and on CD. Speaking of audiophiles, by the time they can afford to buy their must-have equipment, they've already lost their hearing. Give them 128kps mp3 file stamped on vinyl and will swear it sounds better than your original CD :)

Re:CD is the problem, not wma, mp3 or ogg

[norton_I]

Are you sure that the problem isn't in the mastering engineers, not the CD format? Almost all pop music is dynamically compressed within an inch of its life to make it sould louder on cheap equipment. I am told that this is much less of a problem with classical music, but classical music also tends to have a much higher crest factor than pop, and is therefore more sensitive to compression as well.

The noise floor and dynamic range of a CD with a high quality DAC should be better than almost anybody's ears, if correctly mastered. DVD-Audio should be even better than CD, with multi-channel to boot, and also gives recording engineers a lot of headroom in the ultrasonic to avoid aliasing while using low order filters that are in principle somewhat gentler on the sound. SACD on the other hand is a travesty, superbly wasteful of bandwidth, while having less resolution and more noise in the highest octave of the audio range and much, much more noise in the ultrasonic, which is inaudiable, but can have negative effects on the audible spectrum because of effects in the tweeter.

Ripping from the source a disadvantage? Huh?

[pz]

Let's see. Given the task of creating a codec de novo and the financial and political means to have access to the original source material rather than a version sent through a horribly non-linear sampling mechanism out of your control and beyond your specification, which would you choose?

I'm sure most Slashdot readers will be familiar with the Nyquist limit and understand the complete inability to represent information above the limit, but how many are familiar with the degradations that occur near the Nyquist limit when you have non-infinite signal lengths? This is why oversampling is so important. In general, if you have a signal at frequency f that you want to accurately capture, you should be sampling (by rule of thumb) at 5f or greater. If you sample at lower frequencies, the distortions in phase and amplitude are difficult to predict and statistically analyze as they tend to have uniform rather than Gaussian distributions.

So again, I re-pose the rhetorical question: given the task of creating a new codec rather than rewriting an old one, wouldn't you want to use the least-filtered signal possible as a source, especially when the extant filtering is non-linear, and be able to select by design which parts to encode and which parts to ignore? I sure would.

AAC works for me...

[berniecase]

I bought about 10 songs from Apple's music service yesterday, and they all sound great. When I got home, I ripped Would? from Alice in Chains's Dirt and compared it to the 182kbps VBR MP3 I already had. The AAC sounded about the same as the MP3. It didn't sound worse, and I was running this through my iMac G4's audio system and then a pair of Polk bookshelf speakers I have on my desk (and a Pioneer receiver/amp). I'll stick with AAC, and I'll stick with the iTunes Music Store. For my money, it's a good deal.

Under-reported but VERY important distinction:

[mxcantor]

from macslash:

AAC comes with a significantly lower number of b*tching [\.] users than ogg

Re:Ok, here goes...

[Anita Coney]

Sure he's flamebait, but he's right. When I decided to rip all of my CDs and store them on my computer, I tried various formats. MP3, MP3pro, WMA, and yes OGG. In all honesty I could not hear the difference between any of them whether I played them via headphones or through my Sony STR-DE475.

Thus the choice was easy because only one factor remained: ubiquitousness.

Will it work with any portable player I buy, or will my hardware choices be limited?

Will I be able to share them with friends without having to explain how to play them?

Will it work with programs such as Nero without decoding the files to a different format first?

One format fit that criterion and it was MP3. Sure it's proprietary. But so is my car. I'm not going to stop using something that works merely because its proprietary. Computers are tools, not a religion!

Ogg vs. AAC

[Zebra_X]

They simply can't be compared. The reason for this statement is that AAC "supports" or "is encumberd by" (depending on what camp you are in) digital rights management. While they are all formats for redistributing music, OGG is not an option when trying to negotiate with record companies who need some assurance that their music won't be redistributed.

A better comparison would be WMA vs. AAC and OGG vs. MP3.

PNG

[Ender Ryan]

Yeah but, people aren't really switching to PNG because IE doesn't support it. The same is true of Ogg, no hardware support.

So, instead of people doing the intelligent thing and switching to something that is unencumbered by patent liability, people stand around with their pants down and get bent over.

It sure is painful to watch...

Re:PNG

[Ender Ryan]

IE still does not fully support PNG graphics, specifically, it does not support alpha blending, one of the major features of PNG.

Re:Ok, here goes...

[MjDascombe]

Absolutely. I mean, who cares if it's propriety? Sure, it fits in with the nice free-software-is-great mentality, but lets just sanity check that for a second : Who here has a completely legal MP3 collection? With the MPAA charging $125k a track for pirated music, do the technical symantics of the EULA of your music players file format (not the player, the format) matter that much?

If you love free as in sunshine software, and pride yourself on using open protocols your allowed to : STOP COPYING MUSIC. If you want free music, accept your ripping people off, and do the whole job

It just seems to me that with all the self-praising of opensource slashdot does, it's shooting itself in the foot - haven't you seen any of the rocky films ; it's always the underdog who wins ; free software can only improve while people will admit it needs improving, and thats not going to happen with all the brown-noses on slashdot.

Re:AAC is pretty weak, no marketing can change tha

[Halo1]

The quality of an AAC file very much depends on the encoder (it's the same with mpeg4 video or mp3 audio). The test you are refering to only shows that the encoder they used (the one present in Quicktime at that time) was quite bad. It doesn't mean that AAC in itself is bad.

Windows Media player support

[edgarde]

This plug-in enables Windows MediaPlayer to play Ogg Vorbis files. Unfortunately it doesn't support CD burning from Ogg, which (in XP, maybe other versions) is enabled for MP3.

It's an easy install which the average Windows user would perform if so directed.

It's a big plug-in cos it also enables support for Monkeys, ASI and MJPEG. Enjoy.

Re:Windows Media player support

[Anonymous Coward]

It's an easy install which the average Windows user would perform if so directed.

Why is everyone so determined to miss the point? Yes, there are a dozen ways of adding Ogg/Vorbis support to Windows. They vary in complexity.

Support is not available by default, therefore your average non-technical Windows user will get a window popup asking them which application they want to use to open the .ogg file that they've somehow come across and double-clicked on. At this point they will be out of their depth, they'll click on cancel and get on with their lives - ignoring .ogg files from now on, because 'they don't work on my PC'.

problem with sennheisers is...

[EnderWiggnz]

they dont wear-and-tear well... if yer out spinning, the constant nasty wear and tear and the beating that they take will break sennheisers.

sony-600's fer me babeeee - avoid the 700's, as they will damage your ears.

Re:Bose??? Buahahaha

[Reverberant]

First, the subwoofer + satellite model is fundamentally flawed. 20Hz is directional. Bass doesn't "fill the room like fog" -- when a train's coming, you can hear the direction, right?

Umm while I would agree that Bose's implementation of satellites+bass module (to Bose's credit, they don't call it a "subwoofer") has flaws, the subwoofer + satellite principle is not necessarily flawed. If your satellites go low enough (80 Hz is the common figure), a sub/sat system is perfectly workable. See NHT.

Also, it's been pretty well established that frequencies below 80 Hz are non-directional. When you look at the wavelengths of those frequencies when compared with the typical human interaural spacing you can begin to see why. The reason you can hear the direction of a train is due to the high-frequency cues you get from the wheel/rail noise (disclaimer: I spent 7 years working as a noise consultant specializing in rail noise).

How to convert from MP3 to AAC with iTunes 4?

[benwaggoner]

In my workflow, I want to keep a big bunch of high data rate files on the home server (about 140 GB of 320 Kbps MP3 files), and then recompress to more portable formats to carry around on the PowerBook or whatever. This used to work fine. I'd use the Import feature of iTunes, and would convert from the 320 Kbps master file to ~150 Kbps VBR MP3 files for the road. While the lower data rates wouldn't work on my home Paradigm speakers, they were fine for listening to on airplanes.

However, this doesn't seem to work in iTunes 4. I see the Import option, but all the MP3 files in my current library are grayed out. Is this operator error, or does this not work anymore? If not, what is the Import function for?

Obviously I'd like to switch to 128 Kbps AAC-LC for my mobile music. But heck, I'd live with being able to make my old MP3 files!

-Ben

and similarly:

[mblase]

The sound engineers gave a high rank to equipment that produced the sound accurately. The musicians gave a high rank to equipment that made the music clear.

In the same vein, young new-car-owning males gave the highest rank to equipment with the most excessive bass; yuppie parents gave highest rank to equipment that played everything at half speed; and pre-teenagers gave the highest rank to equipment that looped the same four measures over and over again.

Spectrum analysis :-

[jmv]

Spectrum analysis was used to see which format did the best job of maintaining the shape of the original waveform

Will people ever stop doing that. It's complete bullshit and certainly not the way to evaluate a codec. These codecs use perceptual weighting of the noise. That means that the idea is to distort the signal as much as possible in any region of the spectrum where it won't be heard at a certain time. That means that you see a big distortion in the spectrum and think the codec is worse than the others when in fact it's better because it realized that it doesn't matter.

The only way to correctly evaluate a codec is to listen to it. I write codecs (see sig), so I know a bit what I'm talking about. I use spectral analysis sometimes, but only to identify problems which I've already heard before, not to say that my codec is good.

As a aside, I'd say it probably wouldn't be hard to write a codec that does better than any other on those spectrum analysis. They would sound like crap because their psycho-acoustic model would be all wrong.

Re:AAC is pretty weak, no marketing can change tha

[AusG4]

Umm, as a musician and music lover, I can say with certainty that if you couldn't distinguish a 64kbps OGG from an original recording, then you have no credibility and shouldn't be making bold statements like "AAC is very weak".

That said, the fact the the "expert test" yielded better results for AAC isn't surprising.

AAC, at least the encoder that ships with QuickTime 6.2 (and iTunes 4 by connection) does a very good job. Ripping from a source disc or even down converting from a 320kbps MP3 into 128kbps AAC yielded a very listenable file in my opinion... more then enough to please me in a decent pair of headphones or through my car stereo.

Re:Bose??? Buahahaha

[SavoWood]

The problem here is terminology and the understanding of the application of it.

If I put a subwoofer in a corner, pump 40 Hz through it, and stand blindfolded in the room with it, I can point it out. The omnidirectional nature of low frequency transducers is well documented, but the source point is very distinguishable.

Problems begin to arise with very high frequencies in a reflective environment. If I take a HF horn, pump 12k through it, and stand blindfolded in the middle of a metal or glass room, I'd have a much harder time distinguishing the location.

In both cases, if you use a pulse instead of a constant sine wave, the ability to locate the sound is greatly enhanced.

Having worked on a contract for Neumann about 10 years ago or so developing the kunstkopf, I can tell you from personal experience and exhaustive testing, these observations are well documented, but never referenced by people using the satellite systems.

Additionally, your statement about 80Hz being nondirectional can be easily debunked. Meyer has developed a subwoofer system which creates a cardiod pattern from a subwoofer. Also, placing two direct firing subwoofers in proximity to cause coupling, will exhibit lobing thereby becoming more directional. As a monitor engineer who has to stand close to the stack, I appreciate this phenomenon.

Let's not even get on the horn loaded bass cabinet here. That's very directional although huge (the size being one reason for multiple cabinets or the Meyer rig).

Re:AAC is pretty weak, no marketing can change tha

[AusG4]

OK man, you really do have to READ the reports you are referencing first. To quote:

"Ogg Vorbis files were found to be the closest to the reference file by 25% of online testers (as compared to the uncompressed wave file, which was correctly identified as closest to the reference file by 41% of testers)."

This says two things... firstly, that 3000 people didn't actually say "Ogg at 64kbps and CD is identical". It means that of the test group, only 750 people actually thought so. Compare that to the 1500 that weren't deaf and/or retarded and managed to notice the WAV file.

Also, the test itself is completely skewed and clearly biased.

To quote:

"Note that Ogg Vorbis is a variable bitrate format. You can tell it to create files with a certain average bitrate, though. In the test, c't made sure that the different codecs created files of about the same size to give no format an advantage. "

This is a major problem with the test itself. Any VBR file is going to yield better results then it's CBR counterparts when using the same "base bit rate". The fact that they "tried to create files of the same size" demonstrates total misunderstanding of the concept of CBR vs. VBR and nullifies the their "ogg is better" conclusion. I'm not saying OGG isn't a great encoding scheme... but it's not CD-quality-at-64-kbps-great like you've tried to assert.

"shape of the original"

[mnemotronic]

Spectrum analysis was used to see which format did the best job of maintaining the shape of the original waveform

Well, that's one way to do it. Probably the worst way. Critical listening generally doesn't take place with an o-scope or spectrum analyzer display, but via the human ear. Consumer Reports, plus most of the "hi fi" mags, don't seem to understand that. They think that "good measurements" indicate quality reproduction, so they run their square waves through the amplification channel and say "looks good ta me, Vern". Funny thing, but they never try the same test with transducers (i.e. speakers or headphones), simply because they don't want to show how poorly these reproduce the waveform.

Is the iPod fixed yet?

[Richard_J_N]

I found that the iPod does a ghastly job of very high bit rate MP3s (anything abouve 256), where the artefacts become very obvious. This is especially so with classical music with high dynamic range, in the quiet bits.

I confirmed this with several different iPods on different computers, and several listeners. I even got a demo in a Mac store - and even the salesman was surprised.
(I have some sound samples, if anyone wants to offer a mirror for them.)

Richard

P.S. My saga ended up after 6 weeks of technical "support" from Apple concluding that:
1)There is a bug in the iPod - the processor is too slow - and it throws away data it cannot decode.
2)Apple *hate* their customers
3)I got a refund.

Re:maintaining the shape of the original waveform

[AlphaOne]

We compared all the lossy formats to a wav ripped straight from the CD.

It doesn't matter!

Spectrum analysis of a perceptual coding system is useless. The whole idea behind perceptual coding is that certain types of sounds mask others, so therefore you can avoid encoding the masked sounds.

The waveforms will always be different... the better the psycoacoustic model the more the waveform will differ for the same PERCEIVED quality.

But that's not the point... does it SOUND the same to the average listener? Does the perceived quality diminish? Does the audio suffer NOTICABLE artifacts that irritate the listener?

No matter what scheme you use, the answer to all of these questions will be "yes" to some people. But how many people say "yes?"

Each person's interpretation of audio is different... some people are tone deaf, others have a very high sensitivity to artifacts, and yet others are somewhere in the middle.

Spectrum analysis tells you nothing about how well a codec encodes for the human ear because the analyzer is FAR more sensitive.

Re:Bose??? Buahahaha

[SavoWood]

Taking the bass guitar as an example, depending on the mic, the pickups, the amp, and the cabinet, you're going to have a lot of different possibilities on the sound. I've recorded bass with a "woof" sound and with a "Seinfeld" sound, and everything in between. Regardless, if the HF driver was on the opposite side of the room in any of those cases, I'd be able to tell where the LF unit was.

From that LF unit, the waves (depending of course on the frequency) radiate in basically a circular pattern. Yes, I know there are lobes and a slight reduction at the rear portion of the cone and all that jazz. However, the location of the reproducing LF cabinet is easily located using psychoacoustic principles illustrated by the kunstkopf and the various implementations and understandings of the Haas effect.

Did you work on Fritz?

The project would have probably been the predecessor. We went to a lot of cathedrals around Germany and one in Holland to record some really funky sounds using various prototypes of the kustkopf.

As for a reverberant chamber, I used the illustration of materials I did to make it more clear for the less knowledgeable people on the forum who wouldn't have a difficult time understanding the concept using something they can easily demostrate has a low absorbtion and transmission factor and a high reflection factor. As you're probably aware, sheetrock will reflect enough at 12k to produce the phenomenon I described (although not as well as glass *GRIN*).

These problems aren't specific to satellite systems, but all current sound reproduction systems. When you take the drivers and remove them from a single source point, you begin to introduce major timing issues which the average Joe can perceive. Look at the Tannoy web site and the Meyer web site about dual-concentric technologies. When you move the drivers away from each other, you introduce timing differences. I've illustrated this to friends and strangers in the local Circuit City or Best Buy. It's not hard to hear when you stop listening to the marketing hype from Bose. (BTW, "böse" in German means "evil"...just another reason to stay away from that company. heheheh)

When I said "non-directional" I meant in regards to perception, not source characteristics. You can obviously create beam-forming implementations as you describe, and one would be able to hear the difference if one stepped in and out of the main lobe(s). But it doesn't follow that once a person is in the lobe that they would be able to identify the source direction based solely on audio cues.

If you were standing on a forward or downward firing sinlge driver cabinet, you would have basically an equal radiation all around you. However, you'd still be able to tell the cabinet was below you through means other than the fact your feet are vibrating. The studies leading up to and since the naming of the Haas effect will be able to explain to you what I mean.

If you take those same LF cabinets, put them 100 meters away on a giant turntable with you standing in the middle, you'll be able to locate it as it moves around you. You will be able to do the same at 10m and even 1m. So, although the sound coming from the cabinet is for sake of argument, omnidirectional, the source point can still be located. Your brain is still able to determine the location of it in the field around you.

The Haas effect I believe is the ruling factor here. I'd read up a bit on the Meyer site as John Meyer (along with his brilliant staff) has done some amazing studies in their anechoic chamber and in real life situations (Speech Intelligibility Papers) using systems like SIM II where you could acually measure the effect I'm trying to illustrate here.

Re:AAC is pretty weak, no marketing can change tha

[pod]

That only 41% chose the WAV as the best says to me one of two things:
- the listeners don't know what the hell they're doing
- all the formats are pretty damn good
If the compressed formats are able to fool or confuse over 50% of the testers, then we're probably just splitting hairs here.

Re:Bose??? Buahahaha

[Drishmung]

Amen. The aim of speakers should be to be sonicly invisible. If you can 'hear' your speakers, if they make the music sound 'better', then they are not doing their job. Good reference speakers make the walls go away---it's like there is nothing between you and the performance. And the weird thing is that they aren't even particularly expensive. However, they don't sound impressive in the shop. In fact, not sounding impressive is their entire aim in life!

Of course, if you want to play with the sound---pump up the bass, effectively remix the music, go for it, but it's a whole lot easier if your hi-fi is uncritically passing the sound through rather than 'helping' at various stages by adding treble or damping extremes.

Re:Ogg, not OGG

[Ziviyr]

Ogg is the container, Vorbis in the main Xiph audio codec. If you're evil enough you can make Ogg-MP3 or Ogg-WMA. Ogg only implies Vorbis due to common association.

Tremor isn't a codec at all, its a Vorbis playback engine.

You made more nits than you picked. :-)

found an OGG vs. MP3 vs. WMA vs. RA comparison

[Russellkhan]

While googling for the name of a magazine I haven't picked up in years in order to refer to it in my previous posting, I ran into this comaprison of OGG vs. MP3 vs. WMA vs. RA. I thought it seemed relevant an might be interesting to some of you guys.