Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site watdcsu.UUCP Path: utzoo!watmath!watdcsu!herbie From: herbie@watdcsu.UUCP (Herb Chong, Computing Services) Newsgroups: net.audio Subject: Re: Sheffield CDs and why they sound bad Message-ID: <493@watdcsu.UUCP> Date: Wed, 10-Oct-84 19:28:26 EDT Article-I.D.: watdcsu.493 Posted: Wed Oct 10 19:28:26 1984 Date-Received: Thu, 11-Oct-84 06:57:02 EDT References: <460@watdcsu.UUCP> <46@vice.UUCP>, <176@mouton.UUCP> Organization: U of Waterloo, Ontario Lines: 32 Which is all true, but remember that quantization noise is like IM distortion, it is audible at levels that harmonic distortion is not audible at all. I was attempting to point out that there is more to the sound of "digital" that meets the ear. For all intents and purposes, dithering the digital signal itself removes all the problems with quantization noise by randomizing the components of the noise. As for dynamic range offered by a 16-bit linear system being inadequate, it has nothing to do with the continuous output power. One can easily generate a pulse of about 100uS that can require thousands of watts to reproduce accurately, and yet not sound very loud compared to the threshold of pain. Imagine a bolt of lightning striking about 500m away. It has a peak SPL somewhere around 140+dB. You aren't immediately deafened and you don't fall to the ground in pain because the pulse didn't last long enough to transmit significant energy to your eardrum. The oft-quoted SPL's for pain is with a signal that is relatively long-lived by comparison, say one or two seconds. Bob Carver has recognized this and has made his amplifiers to have tremendous reserve power, but only for the short time it is really needed. It works because music is, by nature, transient. He has also observed that, if it were practical to do so, an amplifer capable of peak power more than 2000W/ch for about a mS is needed for accurate peak reproduction with typical speaker efficiencies. Make of it what you will. Herb... Once a hack, always a hack... UUCP: {decvax|utzoo|ihnp4|allegra|clyde}!watmath!watdcsu!herbie CSNET: herbie%watdcsu@waterloo.csnet ARPA: herbie%watdcsu%waterloo.csnet@csnet-relay.arpa BITNET: herbie at watdcs