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Path: utzoo!linus!philabs!polaris!herbie
From: herbie@polaris.UUCP (Herb Chong)
Newsgroups: net.audio
Subject: Re: White Noise on CD's
Message-ID: <193@polaris.UUCP>
Date: Sun, 13-Oct-85 13:36:29 EDT
Article-I.D.: polaris.193
Posted: Sun Oct 13 13:36:29 1985
Date-Received: Tue, 15-Oct-85 07:30:07 EDT
References: <148@birtch.UUCP>
Reply-To: herbie@polaris.UUCP (Herb Chong)
Distribution: net
Organization: IBM TJ Watson RC
Lines: 25
Summary: 

In article <148@birtch.UUCP> ken@birtch.UUCP (Ken Brown x254) writes:
>I don't know if it is true, but my roomate has informed me that the manu-
>facturers of CD's introduce white noise (maybe pink noise) to reduce the
>'spikes'.  CD's will produce a "stair-step" type of waveform, and the
>white (pink) noise produces a flat line (or curve), instead of spikes.
>
>disclaimer: I don't know if its true or just B.S.  (I don't work for no-one
>	    who makes, designs, sells, uses, borrows, steals, or thinks
>	    about CD's)

this is known as dithering and there are few CD players these days
that don't use it.  the overall S/N is reduced, but the quantization 
noise at low levels is randomized so that subharmonics of the sampling
frequency are not audible.

Herb Chong...

I'm still user-friendly -- I don't byte, I nybble....

New net address --

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