>perhaps we should fork this discussion off at some point...... Done. >> I guess, then, that *real* 24-bit resolution, or something very close to >> it, would yield what I am looking for - if it can be achieved. > >Are you sure that's what you are looking for? Well, I guess I would have to hear it to be able to answer that. :) >Fidelity is a measure of how closely the signal you get out of your >recorder matches what you put into it. Agreed. That is all I am after. >It's more likely that you are hearing differences in quality from one >component to the next. I can hear the difference between an Apogee 24 >bit converter and a cheap no-name 24 bit converter. I have no doubt that this is indeed a significant factor . . . >Ah, but there are so many other differences between those effects than >their bit depths. Let me guess, they sound better in the chronological >order they were released in? The amount of DSP available and the quality >of the code has changed too... . . . in fact, I don't have any way of knowing *what* is really in a piece of hardware, regardless of what the specs say, the company that manufactured it, or even how much I paid for it. I only know that some components sound much better than others - I can't say for sure why. If they claim to have a higher resolution, it is of course natural to assume that has something to do with *why* they might sound better. >Can you prove you can hear the difference between 24 or more if >no real 24 bit converter does exist ? It is _extremely_ difficult >and expensive even to do a valid test at 20 bits. Some people >have done it, and they all arrive at the same conclusion. Not without being in a lab under controlled conditions - no, of course I can't prove it. >> Again, what do you base this on? > >Working knowledge of how good analog recording is, understanding of the >theory of sampling and quantisation, undisputed results from >psycho-acoustic >research, and elementary physics and mathematics. I have some basic background in those subjects as well, yet I do not agree. Psycho-acoustics is by its very nature *subjective* - you cannot have 'undisputed' results from this - it is as fallible as any statistical sampling, and as easily skewed. >Yes. A correctly dithered signal converted back to analog is mathematically >equivalent to the original unquantised version plus some noise. There is no >way, not even in theory, to detect it was ever quantised. Since it can't >be detected, you can't hear it. But you could fool yourself into thinking >you can, as many have done before you. After (correct) dithering the only >'defect' that remains is noise. And with 24 bits and standard signal levels >this is well below the thermal noise of any analog amplifier that exists, >and also well below human hearing thresholds. If there is one correct way to do this, then there should be no reason for different 'noise-shaping' algorithms. In fact, why are there different noise-shaping algorithms if the noise can't be heard.? >> I can hear the distortion of the audio signal created by Dolby - and I >> don't like it. > >What has that to do with this discussion ? I merely mentioned that as another example of psychoacoustic masking that supposedly one cannot hear - yet I can. I can also hear the difference between a digital copy and the original sound file, and between the same generation of digital copies on different hard drives. I can hear radical differences in audio quality between CDs burned at different speeds. Theoretically - or mathematically as you wish to present it - I shouldn't be able to hear any of this: they are all mathematically the same, and should sound identical - but they do not. Perception by the human ear and human mind cannot be reduced to a mathematical equation, however much you may wish to do so. There are organic fragrances that never have, and never will, be able to be synthesized, or even distilled - even with the most refined and careful processes - for the same reason. Perception is not mathematical - and that applies as much to that which is perceived as to the perceiver. >Buy some *good* converters, add Ardour and the result is *far* better >than any 24 track analog machine that ever existed. That is if your >idea of quality relates to fidelity and not to some specific typical >analog distortion that you may like or mistake for 'correct'. By 'good' >converters I mean at least the quality of RME, or better Apogee. That, I would be most happy to do. I thought RME was the pinnacle of quality, but if you say Apogee is even better - we will certainly try it (finances permitting, that is. :) >You still probably won't believe me, but the fidelity of a £100 card >like an audiophile 24/96 will be greater than that of 24 track 2". > >The audiophile will have a lower noise floor, better linearity, no >scrape flutter or wow, much lower cross talk between channels, much less >IMD, wider frequency response (and a more solid bass end).... but it >might not sound as 'good'. > >I don't know if you have ever worked with tape, but you really did have >to be so much more careful than digital about getting a good level to >cut down noise, putting non critical tracks on 1 and 24 as they always >got a bit knackered on reels and transport, recording at lower levels if >the source has lots of hf content, line up and bias.... all this stuff >was a total pain in the arse. Most everyone used some kind of noise >reduction, unless they were pushing the tape really hard, in which case >the distortion figures are laughable compared to digital. Yes, I realize that there are all kinds of problems - especially noise - with tape, and it is not the 'perfect' way to record, and I am equally well aware of the great advantages digital has over analog. My point has not at all been to criticize digital recording technology. I want very much for digital recording to match or exceed analog in quality - I am just not yet convinced this has been achieved. >I submit that the perceived 'superior' perfomance of good analog tape >recorders, of any track width, is more a long term ear training result >than anything else, after all, we have been listening to such >machinery, faithfully encoded even on our cd's, and before that on our >lp records of yesteryear, for 3 or 4 generations now. Do that for 55 >years, and the ear thinks thats what its supposed to sound like, >effectively becoming its 'Gold Standard'. You certainly have a good point there - I think there's a lot of truth to that. But what I'm after isn't a perceived 'Gold Standard' of analog recording. I'm just after the most faithful possible reproduction of what I hear live. That is what I mean by fidelity. >That diff of tape or no tape isn't always that obvious, and I had that >hammered into me one evening in about 1961 when I had a chance to >listen to one of Emory Cooks 78 rpm lp's that had been recorded in >trinidad, live to disk, of some of their then infamous steel drum >bands. No tape in the path, straight from Altec M21 mics thru the >preamps & to the cutter head making the master. > >The hair stood up on the back of my neck, it was that real. There was >stuff from the background crickets at 17khz or more that was as live >and real as if I had been standing in the middle of those crickets >myself. Even the whispers of the drummers as they kept each other in >step, probably 55db below the drums, could be heard well enough to >understand it if they were using english, which some didn't. Look - I do understand what you guys are trying to say, and respect the fact that you have some science and experience to back it up. I will just say this: We have an old Tascam portable 8-track, which is now ready for the junk heap, but we got close to perfect fidelity (after a lot of hard work) of what we recorded on it with respect to the live sound. If I wasn't looking, I couldn't tell if my husband was playing live, or playing back his recordings. Our early attempts to record that live sound through our Gina card directly to the hard-disk sounded just plain bad: harsh, strident, thin - cold, but more to the point - not at all like the live sound. The analog recordings have a warmth to them - a midrange 'fullness' that I don't hear digitally. Digital can sound very sterile. (When we attempted this through our earlier Pinnacle Multisound, it sounded like a midi guitar.) When we record now through our hdsp9632, the fidelity is very good - very clean (almost *too* clean), but still not quite the live sound - though very close. When I am unable to tell whether my husband is playing live, or playing back a digital recording of his music - then I will believe that the digital technology has matched analog. If all it is going to take is a better quality AD converter - then I will be thrilled! >I know by now I've bored all the knowitalls here to tears, so I'll go >back to my corner now. > >-- >Cheers, Gene Not at all, Gene, I enjoyed your comments. >Dogma warning: You're not taking all the potential phenomena into >account that have not been scientifically explained yet. > >I'm not saying Maluvia can hear a difference, I'm just saying you don't >know that she can't. Thank you, Carlo. ;) - Maluvia
