Xref: utzoo sci.electronics:10674 rec.video:11170 Path: utzoo!attcan!uunet!ogicse!uwm.edu!cs.utexas.edu!mailrus!iuvax!silver!dschick From: dschick@silver.ucs.indiana.edu Newsgroups: sci.electronics,rec.video Subject: CD's and digital audio (was Why I hate CDs) Message-ID: <38844@iuvax.cs.indiana.edu> Date: 18 Mar 90 01:40:10 GMT References: <1554@redsox.bsw.com> Sender: root@iuvax.cs.indiana.edu Reply-To: dschick@silver.ucs.indiana.edu () Organization: Indiana University, Bloomington Lines: 58 In article <1554@redsox.bsw.com> campbell@redsox.bsw.com (Larry Campbell) writes: >In article bas+@andrew.cmu.edu (Bruce Sherwood) writes: >-The analogy with audio is that a CD with frequency response out to 10 >-MHz would not sound better than one with frequency response out to 20 >-KHz, because the human ear can't hear the higher frequencies. > >Speak for yourself. Perhaps the *average* human ear can't hear higher >than 20 KHz, but some can. I don't know what frequency they are, but >I can hear those "ultrasonic" sonar burglar alarms -- and they are loud >enough to be painful if I'm standing directly under the transducer. >But I know most people can't hear them. > >CDs would have been nice if they had a decent high frequency rolloff; but if >I A/B an LP and a CD it is clear that the CD has cut off the higher >frequencies. So I get a choice -- ticks, pops, and rumble, or missing high >frequencies. Feh. > >Anyone know if DAT will have a better high end than CDs (presumably this >depends almost entirely on its sampling rate)? Indeed, the frequency response depends entirely on the sampling rate. The fidelity, however, of the high frequencies depends on the A-D sampling rate (oversampling), the anti-aliasing filtration, the D-A sampling rate (oversampling again), and the output filtration, among a possibly endless list of other factors. The DAT recorder will sample at a maximum of 48Khz, so it should have slightly better high frequency response than the CD format. (This still won't get us anywhere near the range you are looking for however.) I personally don't have the problem with the lack of ultrasonic frequencies on the CD, but empathize with you nonetheless. Many folks in the music business claim that we perceive (not necessarily hear) these frequencies, and that their absence has a definate impact on the aural experience of the listener. Anyway, if you don't hate the concept of digital audio altogether, and are just fed up with the frequency response limitations of the current generation of gear, you might take a look at Ken Pohlman's "Principles of Digital Audio." It is a fascinating in-depth look at this wonderous new technology. If the people who claim that LP's still sound better - and I don't put you in that group Larry, as you seem to be unhappy with CD's AND LP's - would read this book, they would realize that in the long run, digital audio will satisfy even the most discriminating ears - their own! Presently, it is possible that an LP played on a Linn-Sondek with a whatever sort of tonearm and cartridge can sound better than a CD. But keep in mind that the LP is at the peak of it's evolution. Digital audio is still an infant, and it has almost caught up already! The problems associated with digital audio are not with the digital portion itself, but rather the A-D and D-A conversions. However, we are learning new and better conversion techniques everyday... As this portion of the technology evolves, we will be able to hear the true beauty of digital audio. -- Dan Schick