Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site mouton.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mouton!karn From: karn@mouton.UUCP Newsgroups: net.audio Subject: Re: Sheffield CDs and why they sound bad Message-ID: <176@mouton.UUCP> Date: Wed, 10-Oct-84 11:07:06 EDT Article-I.D.: mouton.176 Posted: Wed Oct 10 11:07:06 1984 Date-Received: Thu, 11-Oct-84 06:54:34 EDT References: <460@watdcsu.UUCP> <46@vice.UUCP> Organization: Bell Communications Research, Inc Lines: 13 On every CD I own, both those recorded from analog masters and from digital masters, the recorded-in noise level from microphone amplifiers, mixers, ventilating systems, etc, exceeds the quantizing noise level by a considerable margin. This provides a "self-dithering" mechanism that completely masks quantizing noise. The only time I've been able to hear quantizing noise on a CD is during a silent passage at the end of a recording where the recording mixer must have ramped the master gain down. The recorded-in noise breaks up and becomes irregular for an instant just before it disappears. Mind you, this is occurring at extremely low signal levels -- my volume control had to be all the way up to hear this. Phil