----- Original Message -----
From: "Tom Fine" <[log in to unmask]>
> Well, I can say how test pressings were used at Mercury Living Presence,
cannot speak for others
> because I never heard the details first-hand but I bet most other classical
shops operated the same
> Test pressings were a tool to make sure the master was correctly plated and
production parts were
> not carrying defects. Plus, since RCA pressed the MLP records (superior plant,
> compounds, Mercury plants never got up to snuff until Philips took them over),
this was a way to
> make sure the plant was doing exactly what they said they would do.
> Test pressings were distributed to the producer, the engineer and the
mastering guys. Everyone was
> encouraged to at least spot-check and the producer listened to every test
pressing all the way
> through, comparing with notes made during the mastering session.
> Now, the fact is that production LPs don't sound as good as the test
pressings, which is why I asked
> my original question -- what makes the production LPs generally noisier and
less punchy? I'm
> assuming that the plants pulled out the "maker's mark compound" biscuits for
the test pressing and
> that production itself wore down the stampers and mothers, and perhaps the
simple act of being
> quickly sleeved effects production vinyl.
> Back in ye olde days, a test LP would arrive as a white-label affair,
identifiable only by the
> cutting marks, in a rice-paper-like sleeve in a paper envelope. There was a
separate test press for
> each side of a production LP. The general way things worked at Mercury, a
clerical person would
> pencil in the catalog number on the white label and distribute copies,
including one for the files.
> When the QC listening was done, it was done with a stop-watch so that times
could be known for
> problem, which were noted. Visual inspection was also done and vinyl "zits" or
> groove problems were measured from edge and noted. The rejection rate was
somewhere south of 10%
> most of the time.
> The same care was taken with mono, because mono out-sold stereo even with
classical music until the
> mid-60's when retailers stopped carrying both formats (see John Eargle's JAES
> Stereo/Mono Disc Compatibility: A Survey of the Problems
> Volume 17 Number 3 pp. 276-281; June 1969
> The record industry is now phasing out the mono disc, and the subject of
compatibility has once
> again been raise as it was with the introduction of the stereo disc ten years
ago. Then, the problem
> centered largely around stylus-groove relationships and considerations of
trackability; this time
> the problem is mainly concerned with the way a pair of stereo channels combine
to yield a suitable
> mono channel.
> Author: Eargle, J. M.
> E-lib Location: (CD aes3) /jrnl6877/1969/6797.pdf
> available at www.aes.org
I suspect there may be some confusion here, because some people may be thinking
of "test pressing" in its 78rpm sense...where test-pressing versions of unissued
takes were sometimes made. These also were made in some cases to see if
(or, if multiple takes still existed in "metal part" form) were suitable for
reissue on LP or in 78-album-set form. I have one of these...a pressed copy of
a vintage Ellington side with an "Internal Use" (or something to that effect)
white label, which bears "OK" and a set of initials.
As well, there are the "Altschuler pressings"...10" vinyl copies of unissued
78 takes, which (as I understand it) were sold to selected collectors...?
Steven C. Barr