Xref: utzoo rec.audio:14482 sci.electronics:7371
Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!pt.cs.cmu.edu!andrew.cmu.edu!jk3k+
From: jk3k+@andrew.cmu.edu (Joe Keane)
Newsgroups: rec.audio,sci.electronics
Subject: Re: Copy protection bit set on my CD player (digital out).
Message-ID: <sYsSd7600V4G80VdtN@andrew.cmu.edu>
Date: 10 Aug 89 20:49:11 GMT
References: <752@palladium.UUCP>,
	<1183@sequent.cs.qmc.ac.uk>
Organization: Mathematics, Carnegie Mellon, Pittsburgh, PA
Lines: 15
In-Reply-To: <1183@sequent.cs.qmc.ac.uk>

In article <1183@sequent.cs.qmc.ac.uk> rabin@cs.qmc.ac.uk (Rabin Ezra) writes:
>The artifacts introduced by 48k sampling of the 44.1 signal (Which should be
>clean of any conversion nosie before it gets out the player) will be so minute
>that I doubt that you could detect them in a really good home setup, let alone
>the noisy environment of a car.

If you do it right, there are no aritfacts.  The original signal contains no
energy above 22.05KHz, so you can represent it exactly with 48KHz sampling.  So
you do some hairy matrix crunching, put them algorithm in ROM for a DSP, and
sell the thing for big bucks.  Oh yes, it happens to have a switch remove the
copy-protection bits.

BTW, i think the choice of 44.1KHz sampling was unfortunate.  I can hear a
22KHz tone, but even if you can't, harmonics in that range still have a
definite effect on how music sounds.  I'll show you sometime...