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Cheap to Audiophile with Simple Hacks
petertrog writes "The IEEE has a story showing how you can turn a cheap DVD player into something that sounds a whole lot more exotic. All you need is a small budget, a soldering iron and a desire to void your warranty."
Wow, an audiophile article from the IEEE. Next thing you know, we'll have witch doctors contributing to the Journal of the American Medical Association.
Strange things are afoot at the Circle-K.
I dunno, my time is too valuable to bother doing the upgrade myself. Better just to buy the high-end at 10x the price and save 100x in the cost of my time.
Ruby Neural Evolution of Augmenting Topologies
That is the first real 'Audiophile' tweaks article I have ever seen. It actually detailed real changes you can make to improve the sound of your equipment.
The only reason people purchase expensive interconnects etc is because those components are very easy to change. NOT because they have a significant effect on the fidelity of reproduction.
To really improve the sound you have to improve power supply, decoupling caps etc, but even though the components are very cheap, it's a lot harder than buying a $500 interconnect cable.
I hope to see more articles like this in the future!
This article is basically an advert for LC Audio (whose own stuff doesn't look anything special - look at the ringing on the scope trace of their wunderkind clock oscillator), mixed in with the usual audiophile crap (where's the blind A/B comparison?) with a healthy dose of stupidity; anyone advocating replacing safety-rated components on the mains side with unrated "audiophile" grade parts deserves to be sued by the first idiot who burns his house to the ground. The mains is a hostile environment, those components are designed to fail open-circuit for a REASON!
Jon.
My $35 DVD player has a digital (coaxial) output, and my PS2 has an digital (optical) output (but, the laser is blown and it can't play disks with even the smallest scratches). Why mess with the electronics inside when you can get the audio data right off the disk into your system?
autopr0n is like, down and stuff.
A signal which comes out cleaner on the scope, up to a certain point, will also sound better to the human hear, but past that point, it just comes down to preference. This is why studio engineers often add "color" to a song, and why some audiophiles still swear by vaccum tubes. The vaccum tubes don't produce anywhere near a flat frequency response through the 20kHz range, but instead color it in a way that people describe as "warm."
The point is, you can try and make changes to flatten the frequency response as much as possible, but it may NOT be the sound output you're looking for. The scope would, of course, be useful to track down problems with power supply noise, but when it comes down to swapping op-amps or other stuff, it's often times more subjective than not, which is what his article says. Here, seeing the scope output is useless, because the only important this is whether you like the resulting sound output.
I'd like to agree with you on the part about the clock though, but I have never looked clock outputs when they get shaken/etc, so can't really comment.
- Making the power supply filter capacitors "20% bigger" is a silly idea, for MANY reasons:
- Most electrolytics come with a -20% to +100% tolerance. Because of their construction, it's hard for the manufacturers to get them much closer than that.
- Plus in any well-designed power supply the capacitors are intentionally chosen a bit oversize to handle 50Hz or low line voltage situations.
- Electrolytics have a steep cap versus temperature curve. The engineers know this and specify 40% bigger caps to handle the times you use your CD player in Alaska.
- The filter caps are isolated from the audio circuits by a voltahge regulator chip, which provides about 60 to 90 db of isolation. There's just NO WAY one can notice the effects of a 20% change in capacitance, when the effects are mulffled by a factor of a million to a billion.
- The original filter caps have to be very specially chosen for compatibility with the high frequencies and ripple currents. Is it likely the average joe tweaker is going to choose something that approaches what the actual power supply designer chose? Not likely.
- Replacing the power supply diodes with "faster" ones is a waste of time and money. Any noise the old diodes generate (if any) is many decades above thre audio range. Plus the CD player has to pass FCC emission limits, so they can't be too noisy to begin with. Skip this mod.
- Changing op-amps is really ridiculous. Op amps are always used with huge amounts of negative feedback, which reduces their individual quirks and distortion by a huge factor. I've worked with dozens of op-amps, and have never found one that's not capable of handling your typical audio. A typical 30 cent op-amp already has about 0.001% distortion, thousands of times lower than a golden-eared indivuidual can discern. Skip this step too.
- Tapping into the DAC outputs is a REALLY bad idea. Apparently this guy hasnt a clue about Nyquist limits and sampling rates. You HAVE to filter the output of the DAC's, as they're intrinsically rife with sampling-rate related harmonics and aliasing. Those op-amps are there for a reason!. Don't even think of doing this.
- Putting caulking on the crystal is wet-your-pants funny! There's absolutely no need for this. Crystals are designed to resonate at one frequency. They're totally insensitive, by factos of a billion or more, to any other vibrationary frequency. As an example, there are very precise aerospace radios, with dozens of crystals, none of them caulk-damped, used for life-critical navigation and landing systems, and they work just fine for decades of constant use in vibraty, shaky old prop planes. Put the rope caulk around your windows, not on your crystals.
- If you like the look of gold-plated jacks, install them. There will be absolutely no discernible difference in the sound, but they look neater.
Sorry to rain onthis guys parade, but IMHO there should be at least a token nod towards reality.