Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site brl-tgr.ARPA Path: utzoo!watmath!clyde!burl!mgnetp!ihnp4!houxm!houxz!vax135!floyd!cmcl2!seismo!brl-tgr!mike From: mike@brl-tgr.ARPA (Michael John Muuss) Newsgroups: net.audio Subject: Re: CDs don't you just love them?? Message-ID: <3051@brl-tgr.ARPA> Date: Sun, 17-Jun-84 17:09:32 EDT Article-I.D.: brl-tgr.3051 Posted: Sun Jun 17 17:09:32 1984 Date-Received: Fri, 22-Jun-84 08:45:58 EDT References: <4@sunybcs.UUCP> Organization: Ballistics Research Lab Lines: 29 Charles Pearson asserts If they are sooooo good, them how come they naver can produce a square square wave? My NEC 803 produces a marvelous square wave. While 44.1 khz is woefully inadequate in my opinion, the NEC's technique of replicating the samples and then dong digital filtering, and running the DACs at a much higher rate with the (digitally) filtered result avoids all of the high frequency problems that most CD players are guilty of. The Philips machine uses this technique too, although I have heard tht they had to use 14 bit DACs instead of 16 due to the higher data rates needed... It is difficult to see how a test disk written by computer is likely to NOT have a perfect square wave on it -- my test CD does. As for the validity of testing auudio equipment with 20 khzsquare waves, Charles is RIGHT ON. *I* can hear the difference between a 20 Khz square wave, and a 20 Khz sine wave. The only difference is due to sine wave components at frequencies > 20 Khz. Therefore, extended frequency range is VITAL to accurate reproduction of very high frequency sounds, esp. percussion. This includes having speakers that are capable of reproducing the high frequencies, too. (My Infinity Quantum-2's are flat to 30 Khz, and gradually roll off beyond that. My Kenwood High Speed amp is flat to > 100 Khz. Even my Ortofon MC-20FL cartridge is fairly flat to about 25 Khz.) -Mike Muuss