Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!usc!sdd.hp.com!caen!uwm.edu!csd4.csd.uwm.edu!info-high-audio-request
From: jfw@neuro.duke.edu (John F. Whitehead)
Newsgroups: rec.audio.high-end
Subject: Re: Twenty generations of DAT copies...
Message-ID: <10051@uwm.edu>
Date: 8 Mar 91 13:37:15 GMT
Sender: news@uwm.edu
Lines: 36
Approved: tjk@csd4.csd.uwm.edu
Originator: tjk@csd4.csd.uwm.edu


In article <9981@uwm.edu> tristram%conan.asd.sgi.com@SGI.COM writes:

>>See Mix, April 1991...
>>
>>A panel of three "golden-eared" producers were unable to
>>reliably distinguish approximately one third of the material from an
>>original (one-generation) source DAT.

In article <10017@uwm.edu> Mithat F Konar writes:

>If you re-read the conclusion, you'll discover that the panel was able
>to reliably distinguish a difference between the copy and the original
>on most material. What they didn't do reliably was indicate correctly which
>was the original and which was the copy.

However, on certain types of material they were indeed able to differentiate
between the original and the copy.  For instance, the original solo trumpet 
and the solo voice were generally picked correctly.  The denser or more
obscure types of sound, including music ensembles and sine wave sweeps,
were the ones more often chosen incorrectly.  The differences in sound
were attributed (in their opinions) to phase problems from the repeated
copying, which noticeably (although not significantly) degraded the sound
of the solo instruments.  The denser music masked any phase problems so
they could not reliably pick the correct one.

An interesting note is that none of the engineers seemed particularly 
fond of DATs -- i.e., they do not rely on them/use them extensively in 
their own applications.  But one did say that he would now not have any 
problem with making a dub from the analog outs since the sound degradation
is so insignificant.

    John Whitehead                     Internet:  jfw@neuro.duke.edu
    Department of Neurobiology                    jfw@well.sf.ca.us
    Duke University Medical Center     Bitnet:    white002@dukemc           
    Durham, North Carolina