Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site alice.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!alice!dsj From: dsj@alice.UUCP (David S. Johnson) Newsgroups: net.audio Subject: Digital Trojan Horse? Message-ID: <4189@alice.UUCP> Date: Thu, 22-Aug-85 08:40:36 EDT Article-I.D.: alice.4189 Posted: Thu Aug 22 08:40:36 1985 Date-Received: Sat, 24-Aug-85 15:49:45 EDT Organization: Bell Labs, Murray Hill Lines: 34 Has anyone else on the net heard of/thought about the claim that digitally recorded (vinyl) LPs are destroying our turntables? This hypothesis is argued in Neil Levenson's audiophile column in the May/June 1985 issue of FANFARE (Levenson is a golden ear who would do THE ABSOLUTE SOUND proud). He claims that digitally recorded vinyl discs generate ultrasonic products not present in analogue discs (he claims these have been measured), which somehow cause micro-cracks in turntable bearings (he claims these have been seen under electron microscopes) which by some mechanism greatly increase the short-term speed irregularities of the turntable, especially audible on piano music. Buttressing this argument are claimed measurements of these speed irregularities, on a variety of new turntables. Measurements were supposedly made both before and after digital records had been played, with analogue records used as controls so that the effect could not be due just to playing ANY record. 2-4 hours of digital play is supposedly enough to have a noticeable effect and 12-15 is disasterous. The effect does not go away and applies to all subsequently played records, both digital and analogue. The implication is that the digitally-recorded LP is something of a Trojan Horse: take them into your house and they will destroy your turntable, thus making it necessary for you to buy a CD player, since if nothing else CD players are rock-solid with respect to speed accuracy. (According to Levenson there IS nothing else; he is of course firmly in the anti-digital crowd.) Do these claims about speed accuracy damage seem at all plausible to the experts on the net? David S. Johnson, AT&T Bell Laboratories