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From: david@agora.rain.com (David Robinson)
Newsgroups: rec.audio.high-end
Subject: Re: Twenty generations of DAT copies...
Message-ID: <10142@uwm.edu>
Date: 12 Mar 91 13:47:51 GMT
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In article <10123@uwm.edu> ed@mtxinu.COM (Ed Gould) writes:
>> ... the Chesky test CD has a track which is a 100th generation copy
>> of a digital tape.  You can compare the copy and the original.  To
>> my ears the copy sounded muted and less detailed.
>
>This seems very odd to me.  Has anyone tried to do a *digital*
>comparison of the multi-generation digital copies (which ought to
>be identical, no?) to see if there really are any differences?  If
>there are no digital differences, then I would have to conclude
>that any sonic difference is psychological.  Could there be any
>other explanation?  If there are differences between the digital
>data, is this due to lack of error correction or something truely
>insidious?

I'm not sure that the problem is in the digital domain (01001001 and all
that), since the numerics check out.  

My personal suspicion is that there may be some "drift" in the time
domain...along with an exacerbation of "digititis" due to a "squaring of
the squared sonic wave"^100.  Too much stair-stepping, and not enough
curve, repeated over and over...the numbers can still "match" (*love*
that rounding!) but be imprecise sonically.  

This would be akin to multiple generations in the analog domain building
up hiss and 60 Hz layers; the music is still "there," and is still "right,"
but is fighting sonic drift.

Disclaimer:  My thoughts here are more visceral than analytical.  Comments?

david@agora.rain.com