From: Claude LaPointe  <lapoint@adios.brl.mil>
Newsgroups: rec.audio.high-end
Subject: turntable set-up
Date: 13 Oct 92 14:13:51 GMT
Organization: University of Wisconsin - Milwaukee
Distribution: usa
NNTP-Posting-Host: 129.89.7.4
Source-Info:  From (or Sender) name not authenticated.
Originator: tjk@csd4.csd.uwm.edu



Some months ago I purchased a new AR ES-1 turntable (the one with the
saphire bearing) and am now putting it into service. I'm using the
Blue Point cartridge.

I have a problem, perhaps just a question, on which I would like
comments.

The dealer (who I really have no reason to doubt - runs a small,
by appointment except Saturday & Sunday, hi-end shop, is very
knowledgeable) set it up and installed the cartridge.

I thought I'd check the overhang, which AR states is to be 1.5cm.

The gauge which came with the tt is a thin rectangular plastic sheet
with a hole for the spindle and two sets of line patterns, each
like a group of nested rectangles. The istructions on the gauge are
painfully brief, stating that the guage should be mounted over the
spindle, and the cartridge adjusted (and the tt rotated as necessary)
so that the cartridge's front and sides line up with (are parallel to)
the lines in the pattern. The instructions do not state whether this
is to be done with one (which one?) or both patterns. Currently, this
adjustment is correct for one of the patterns, but slightly off for
the other. It seems to me that, if I correct the adjustment for the
other, I will no longer be in correct adjustment on the current set.

The plot thickens. The gauge described above is not the one discussed in
the instruction manual. I wrote the company, and they sent me the gauge
described in the manual, stating that I should discard the other gauge.
(Why did they provide that gauge in the first place?) This second guage
is long and narrow, made of transparent yellow plastic, about 5 inches
long, pointed at one end, has a raised part with a small hole to accept
the stylus at the other end, and has a hole for the spindle about an inch
inboard of the stylus hole. The instructions state that the gauge is to
be placed over the spindle with the pointed end pointing at the tone arm
pivot point, and the cartridge positioned so that its sides align with
the sides of the headshell and the stylus rests in the hole on the gauge.

Currently, the stylus is about .8cm beyond that position, and there
does not seem to be sufficient room for adjustment in the cartridge's
mounting to move it by that much. I removed a thumbscrew which seemed
to allow the headshell to be repositioned (or at least removed), but it
would not move freely, and I did not want to force it. The instructional
manual is silent about removing/adjusting the headshell.

The dealer states that he adjusted everything correctly with an Oracle
gauge, which is the only thing he has used "for years" on all his
tts. He is somewhat set in his ways, and gave the impression that he
wished not to discuss it further. I am willing to push the matter with
him, even to the point of damaging relations if necessary (I did purchase
about $8000 worth of components from him, and I believe a little more
of his time is not an untoward request), but I thought I would pursue
this avenue first.

The dealer's opinion is that, Oracle being what it is, I certainly
won't go wrong using an adjustment made with their gauge. It seems to
me that this attitude presupposes that all tts with pivotting arms
are manufactured with the same pivot-to-spindle distance and the same
"optimal" pivot-to-stylus distance. If this is the case, then the only
variable is how a company's engineers perceive this "optimal"
pivot-to-stylus distance - after all, the stylus on a pivotting
tone arm tt cannot track tangentially all the way across the record.
Presumably, Oracle being the wonderful tt that it is, their engineers'
perception of "optimal" will yield at least as good a tracking geometry
as AR's.

Specific questions:

Does it make sense to use the Oracle setting on the AR tt?
If not, how can I shorten the pivot-to-stylus distance on my
  AR by about .8cm?
Does anybody have a comment about the 2 different gauges provided
  by AR? Which is preferable? I the one with the line patterns,
  are both sets used, or just one? Which one? If both, how does
  one adjust on the second without screwing the adjustment on the
  first?


Thanks.