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Re: [ARSCLIST] Wax chatter, WAS: [ARSCLIST] Recording Speed
From: Patent Tactics, George Brock-Nannestad
Will Prentice had cought something odd from Mike Biel:
> Mike B said:
>
> <snip>... Unless you are
> thinking about the high pitched chattering that sometimes is recorded on
> wax master discs that get too warm. Since these are heard especially on
> early Victor Orthophonics, they are often called "His Master's
> Dogwhistle". <snip>
>
> I'm familiar with a similar phenomenon, occasionally heard towards the
> end of acoustic sides, becoming gradually louder. This was explained to
> me as "cold wax chatter", a product of insufficient pre-heating through
> of the wax blank, often done in the field (aka hotel room etc) using a
> portable cabinet with paraffin burner in the bottom. The waxes had to be
> heated gently over several hours before they were ready, and it's not
> hard to imagine them being underdone on occasion.
>
> Mike, is this the same phenomenon, or some kind of equal and opposite
> thing?
>
----- In my view, this is what it is about. The wax getting colder, not
warmer, towards the end, where the linear cutting speed becomes too small and
hence generates chatter. To try to avoid this, the Gramophone Co. put a lit
incandescent lamp inside the recording machine.
And, incidentally, I believe that this is the reason for the Pathé records
being cut from the inside-out. They used a copying method (I shall not bore
with details here) that required the master cylinder to be quite close to the
record that was cut. The cylinder could not tolerate to be heated, because
then reproduction would create permanent distortion to the original groove,
so they would have to be careful about how warm they made their disc wax. As
it cooled down, you could compensate for the higher hardness by increasing
the linear cutting speed, and that is what they did. I have not found any
documentary evidence for my assumption.
Kind regards,
George