View Single Post
Old 7th October 2009
Louder Than Liftoff
BradM's Avatar
My friend, you have basically summed up perfectly all the same conclusions I've come to myself in the last year after having spent countless hours A/B'ing analog recordings to digitized recordings in numerous permutations (I provide a link to some tests I did in a bit). I wholeheartedly agree that the reason that ANY digital recording sounds "bad" is because modern PCM conversion (especially at 44.1k and 48k sampling rates) cannot reproduce an analog signal in a manner that is 100% acceptable to me. I say "any digital recording" because I've found that this behavior is not limited to purely ITB mixes, but instead occurs with any recording where individual tracks are digitized before they are mixed (summed) together. The negative artifacts are most pronounced at 44.1k and 48k. Working at 88.2k or 96k seems to alleviate some of the "bad" stuff. I believe George Massenburg strictly works at higher sampling rates for very similar reasons.

I confess that I do not have experience with absolute highend converters (prism, lavry, dad...) but every other AD/DA converter I have tried cannot cope with original analog signal. Something is always lost, and that little "something" is a big deal when trying to mix 32channels of audio.
But this "something" is only evident after recording analog source. If I record digital source, the recording is perfect. (once I tried DA/AD loop, 5 cycles, and it was perfect).
I have experienced the exact same thing. Something does indeed change. To my ears the A/D conversion process doesn't accurately convey the sense of space, depth, and realness that exists in the orignal analog source. I have even found this to be true using high end Mytek conversion so I know the issue isn't limited to lower end gear. And like you have pointed out, once you have a digitized source you can easily convert and reconvert that signal with multiple ADDA loops and suffer no additional audible degradation. Those transfers are perfect. That's because you already degraded the signal to the point of no return during that initial conversion from the analog realm to the digital realm, and this is why I now strongly believe that the first time you convert should be as late in the game as possible (during mastering) and should be with the best converters you can get your hands on. You only have one shot to get it right.

Some say the problem with digital is ITB summing. Others say it is intersample peak distortion and gain staging. Other say it is lack of distortion and color. The problem to my ears is simply that current PCM-based A/D conversion changes analog audio into something that is musically degraded. It's as simple as that for me. Dave Amels of Bomb Factory and Anamod fame, has made similar statements in these forums. He knows a thing or two about DSP processing. I've found DAW summing to be perfect. It's flawless. It works beautifully. If I want color it's super easy to hang a transformer coupled piece of hardware on my 2-buss. If I could have converters that captured an analog source perfectly then I would have no hesitation mixing ITB. Total recall is an absolute dream. Who doesn't want that? IHMO the loss happens before the signal gets to that DAW summing bus.

Here's a test I performed that is very similar to what you are asking for. I think I linked the right one. If not then I'm pretty sure it's in that thread somewhere. I suggest reading the whole thread if you have the time because I posted a number of small tests regarding related issues that you may find interesting (i.e. summing of tracks pre and post conversion)

I know some say digital has arrived. I will say digital has arrived when there are many affordable A/D converter products on the market that accurately reproduce an analog source in a musical manner. One or two products from boutique manufacturers costing $10k or more is a teaser at best. Maybe we should start a pool to guess the year I'll make the switch back to digital.