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Re: [ARSCLIST] (Fwd) [ARSCLIST] Fwd: Recording Speed

Re: pilot tone.  Is this what is recorded on some Euopean acoustics  back 
in the early 'teens?  If so, what is their pitch?
Don Chichester
In a message dated 6/23/2009 2:58:27 P.M. Eastern Daylight Time,  
mbiel@xxxxxxxxx writes:

From:  Doug Pomeroy <pomeroyaudio@xxxxxxx>
> Thanks Mike.
> I was  most confused by George's reference to "the counter", which
> appeared  with no explanation that I could find.

It was hidden away a few  sentences earlier, at the end of the second
sentence of the part I'm  reprinting below.  

> > The frequency of the calibration  track? It was calculated to be
> > 10 times the rpm of the turntable,  in other words, at 78 rpm it
> > gave out 780 Hz, suitable for a  frequency counter. In use of the
> > tape as a secondary master, the  content could be de-chipmunked
> > by changing the speed of the tape  recorder, and the tape rewound
> > to the calibration track, which  was measured by the counter and
> > would give the rpm of the  original record at the de-chipmunked speed.

> It is much simpler  than I thought.  Doug

I believe as turntables with internal speed  counters became more common,
George backed away from mass producing the  little calibration discs, but
now more than ever with digitization of  recordings being made without
documentation of rotational speed, this would  be a quick and easy way to
supply a notation of rotational speed in just  one extra step.  If all
records had been made with a reference tone  like the Seresate records,
things would be so much easier!   

While we are on the subject of using known frequency tones to  determine
speed, the ARSC presentation of the Early Sounds project  explained that
Leon Scott's Phonautograph continuously recorded a tuning  fork tone
alongside of the sound, which now enables the constant speed  playback of
these hand-driven pre-tinfoil recordings.  This is now  called the "Pilot
Tone" system, and is still used to synchronize  sproketless-analogue tape
sound with motion picture film.  I don't  think this has ever been
discussed, but not only did Leon Scott apparently  invent sound
recording, he also apparently invented the Pilot Tone speed  resolution

Mike Biel  mbiel@xxxxxxxxx   

> Date: Mon, 22 Jun 2009 11:23:26 -0700
> From:  Michael Biel <mbiel@xxxxxxxxx>
> Subject: Re: (Fwd) [ARSCLIST]  Fwd: Recording Speed
> I understand what George is saying  partially because I've seen him 
> do it and I am lucky enough to have  one of his calibration discs.
> In case Doug and others still do not  understand it, Doug's snip
> cut out the important info and left in  material that has no
> meaning without the snipped  part.
> In 1982 George commissioned a 7-inch pressing  made of a 450 Hz. 
> tone cut at 45.0 RPM. That disc can be played at  any RPM and a frequency 
> counter will show a reading that is 10 times  that RPM. (Play it at 73.7 
> and it shows 737.0 Hz. 78.26 shows  782.6 Hz. Etc.) If you have a 
> frequency counter handy, you can find  what rotational speed you are 
using. BUT,
> if you include a few seconds  of that calibration disc played on the 
> same turntable at the time of  your transfer of the record you are 
> working on, then later on that  frequency can be read with a counter and 
at any 
> time you can  establish the rotational speed you used. It's like an 
> strobe  disc that has the unique ability to be recorded, and it is as
> accurate  as your frequency counter is. Sure, you could use a normal
> test disc  of, say, a 1000 Hz. tone, but George's disc is more directly
> readable  without using math to have to determine percentage of 1000 
> Hz.  whatever tone you used.
> Mike Biel mbiel@xxxxxxxxx 

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