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Re: [ARSCLIST] jargon



OKeh, but what speed do Gennetts spin at?  Did they advertsie 80 RPM?
I've pitched some at even higher speeds when they didn't match A440.

Any insight to Gennett speeds would be much appreciated.

DS

>>> goldens2@xxxxxxxxxxx 08/21/03 10:14AM >>>
It'd be nice if those of us who are serious about phonographic disk
and
cylinder recordings were to CEASE using the word "speed" for the rate
at
which a disk or cylinder turns.  Speed (velocity) is distance divided
by
time. (i.e. miles per hour, inches per second)  "RPM" is not a speed.
Also,
the turning rate should not be referred to revolutions per minute,
because
they don't revolve: they ROTATE.  Notwithstanding the early (referring
to
the manufacturers of machines and records)  lingual mangling of
"speed",
"RPM" in geometrical and mechanical fact means Rotations Per Minute
except
for those disks in which the speed remained constant & the rotational
rate
varied.  Because the speeds of a preponderance of disks  (consumer,
ETs,
film soundtrack) continually change, it's best to refer to their
RPM's,
whether the user etymologically discriminates between "rotation" and
"revolution" or not.

i.e.  Assuming a 16" disk turning @ 33 1/3 has its outer most grooves
3/16"
from the edge & 5" from the center, its speed range would be determined
by a
maximum dia. of 15 5/8" (15.635") and minimum of 5".  Its speed range
would
be 27.27 down to 8.72 ips!

i.e. Edison DD 52200's (one of my favorite Happiness Boys disks) outer
most
grooves have a dia. of 9.25" & inner most of 6".  Thusly its speed is
38.72
ips down to 25.12.

Note that cylinders also rotate, they don't revolve.  Warping
notwithstanding, given that their playing diameters don't change,
their
speeds are constant.   A 2" cylinder cut @ 120 RPM has a speed of 12.56
ips.
At 144: 15.07 ips. At 160: 16.75 ips.  Assuming that a Concert
cylinder's
playing surface is actually 4", then at 120 RPM those puppies run @
25.12
ips.

Now let's think about those damned ubiquitous "Drive Slow" signs....

Best,
Shiffy


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