ORIGINAL: Joe Bravo
I have an old ADAT that records digital audio to analog tape (VHS) at 48kHz. It is definitely recording not fewer than 48,000 cycles per second, and it is doing it with pretty damn good accuracy.
If you think that has anything to do with recording a frequency at 40k then there's a thing called Nyquist Frequency you need to learn about.
Um, no. The ADAT is recording an ANALOG signal to magnetic tape. There is no "Nyquist Frequency" with analog. There are no samples. This is just a smooth wave of alternating current recorded as magnetic impulses. If someone wanted to transfer the ANALOG singnal imprinted on the magnetic surface of the ADAT tape to digital and do it accurately, then the Nyquist theorem states that they'd have to use a sample rate of at least 96k. There is no sensical application of the Nyquist theorem to an analog signal, because, by definition, there is no quantization in analog.
I didn't ask if you could record a 0 or 1 Hz signal. I asked what analog tape machine could record from 0 to 40k. Not a few of the signals in between. And obviously we're talking about analog signals. So lets get real.
Fair enough, but I never said that I knew of a tape machine that could do this-- I said that the medium itself was capable of it. Just as digital audio is technically capable of better fidelity than any digital recorder has ever actually achieved.
I have never used ANY analog device that had better frequency response or lower noise than even cheap consumer digital gear. But I have also never used a digital device that didn't have distortion from jitter, quantization error, and truncation error, none of which are anywhere to be found in analog gear. Maybe you think that those types of distortion are less important than any distortion in any piece of analog gear. Maybe you think (as I do), that these are tradeoffs that we make and that you're lucky to have such miniscule things to quibble over in selecting from such awesomely powerful tools as we have available today.
The main point I was trying to make (and I realize I lost the forest for the trees and failed to make it clearly) was this: all of this business of the exotic theories of ultrasonic harmonics affecting listener perception and so on were SPAWNED, or at least thrown into widespread discussion, by the percieved inadequacies of digital, which was supposed to be perfect, but was found lacking by a lot of people who are in a position to know. Prior to complaints about the "sterility" or "grittiness" or "harshness" of digital audio, nobody cared much about this stuff except for people in rarefied circles of audio expertise. Now you have sixteen-year-olds whose ears are already blown out anyway debating why the Screaming Labias sound better on vinyl. Maybe they're all idiots, but they have some experts with impeccible credentials taking their side.
Those of us who are here on these forums, and looking for ways to use inexpensive digital devices to achieve high fidelity recordings are on the cutting edge of a fuzzy and evolving science of sound transduction and reproduction.
Not so much. Digital recording hasn't changed much at all in 15-years or so.
No, it hasn't. But the discussion and theory about audio transduction has, and the focus on higher sample rates that the Nyquist theorem says don't make any difference, but that pretty much everyone agrees DO make a difference, illustrates the fact that the issue is far from being closed, or even fully understood. There are people debating WHY 192k sample rates sound different than 44.1, but nobody is seriously arguing that they DON'T sound better (or at least different), even though the Nyquist theorem tells us that they sound the same.
Theories as to why some very knowledgeable people still preferred analog abounded-- some theories were stupid, some were brilliant. ...
Actually, most of it was kind of dumb I think. Neil Young had a point back then because that was in the early days if the CD when it was still 14-bit. And as most of us older guys will recall, when the first generation of 16-bit decks came out they sounded worse than the 14-bit decks before them. Young had a legitimate gripe. After over-sampling was introduced it changed everything and most of the complainers soon stopped complaining.
Joe, I am really not trying to pick a fight here. I agree that a lot of the theories that purported to explain why digital was better or analog was better were pretty stupid. You are entitled to your opinion that the "bass bump" is why people like analog better. But I swear to you, there are a whole lot of people who would still prefer the analog even compared with a digital recording that had an identical "bass bump" dialed in.
I have no opinion on whether being able to record subsonics or supersonics is a good thing or a bad thing, or whether it even matters, and I have no opinion on whether the realtionship between higher sample rates and jitter reduction is what makes higher sample rates more pleasing to most listeners, or whether different kinds of cutoff filters are responsible for phase smear that causes "digital grit," or whether the soothing effects of tape hiss and even-order harmonic distortion are what makes somepeople like analog better. I am not even close to an expert in psychoacoustics. But I do have pretty good hearing, and pretty good "ears," as they say, and I have had the experience of hearing high-quality analog recordings that sounded, to my ears, not just more "pleasing," but also more "real" than anything I have yet heard on digital. That is to say, I have heard reproductions that overall, more accurately created the illusion of sharing the space with the source sounds.
Maybe I just never heard a good enough digital recording on a digital playback system. I fully accept that this is entirely possible. In fact I think it's probably true. I tend to suspect that we are a few years away from putting the debate entirely to bed as higher sample rates and bit depths and better converters and more stable word clock occilators continue to improve digital recording.
But the really good analog recordings that I am thinking of have an appeal that has nothing to do with "warmth" or a fuzzy "lo-fi" appeal. I am saying that they were, to my ears, the most convincing and lifelike recordings I have ever heard. Maybe, if you heard them, you'd disagree. Maybe you can "prove" that they weren't a convincing or lifelike reproduction, but I'm not sure how you'd do that.
I've got nothing against analog recording. But if I saw a guy with a studio around town advertising his studio as somehow being better for recording to tape I'd accuse him of false advertising.
I agree. Analog is different from digital. There are types of distortion that are unique to each, and inescapable in each. Just as charcoal drawings are different from watercolors, what makes one or the other a winner is how it is handled by the artist.
Cheers, Joe.
post edited by yep - 2005/08/02 00:48:32