RE: arsclist New subscriber / LP restoration question

["Copeland, Peter" <Peter.Copeland@xxxxx>]

Dear Michael,
    My contribution is to recommend *elimination of distortion at source*.
That is :
(1) Have a number of LP styli of different sizes and shapes (including at
least one line-contact one), selecting one which avoids touching (what might
be) damaged parts of the groove;
(2) In order to reproduce LPs mastered before the vertical tracing angle of
stereo LP discs was standardised at fifteen degress in about 1965, mount the
turntable in trunnions so it may be tilted, and listen to the S signal and
adjust the vertical tracing angle for minimum distortion;
(3) Remember Walton's paper, which demonstrated that the distortion caused
by a large tip radius ( = "blunt") was almost exactly opposite to the
harmonic distortion caused by a massive stylus modifying its course by
deforming the groove wall. The fact that two types of distortion neutralised
each other was often used deliberately, but at the cost of permanent damage
to the grooves. This accounts for why so many "pop singles" were (and still
are) recorded at such high volumes.
    All this is described in the NSA's operational manual; but it's such a
complex matter that I don't want to bore other readers of this listeserver!
However, I shall conclude with a piece of personal hocus-pocus. I have often
found the distortion you describe may often be reduced by playing a vinyl
disc while it is *wet*. I don't know any technical explanations for this.
But trying to cure distortion "downstream" (sorry about that metaphor!),
seems to me a very second-best solution in principle.
Peter Copeland 

-----Original Message-----
From: X. Michael Warren [mailto:moths_careening@xxxxxxxxx]
Sent: 16 January 2002 18:21
To: ARSCLIST@xxxxxxxxxxxxxxxxx
Subject: arsclist New subscriber / LP restoration question


Hello, all.  My name is Michael and I'm an lp restoration
hobbyist who enjoys spending his Saturdays transferring
records to PC then CD.

I have a question regarding restoration, and please refer
me to the listserv archives if this topic has been
discussed before.

On the loud sections of some of my records there is a
sibilant distortion that I presume has been caused by
previous owners and their dull needles.  Is there a way to
eliminate this sound?  I've tried many different PC click &
crackle removers as well as de-essers, noise reduction and
all manner of minor adjustments on my turntable and preamp.
 It is most exasperating to not be able to remove this
sound.

I will be most grateful to anyone who has experienced and
overcome this problem & who can help me minimize or
eliminate it.

Thanks very much,
Michael Warren
Nashville

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