----- Original Message -----
From: "Art Shifrin" <[log in to unmask]>
> 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.
> 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
> from the edge & 5" from the center, its speed range would be determined by
> maximum dia. of 15 5/8" (15.635") and minimum of 5". Its speed range
> be 27.27 down to 8.72 ips!
> i.e. Edison DD 52200's (one of my favorite Happiness Boys disks) outer
> grooves have a dia. of 9.25" & inner most of 6". Thusly its speed is
> 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
> 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
However, there were a handful of constant-linear-velocity disc recordings
made, and an attachment which enabled users to play them...hardly a
resounding success, though!
In any case. these battles for vocabularic accuracy were probably long
since lost! Keep in mind that "phonograph" originally described only
Edison's cylinder machine...that "LP album" is oxymoronic except when
describing multi-disc sets of 33-1/3 rpm phonorecords, IF they were
packaged in an album rather than a box (likewise "CD album," which at
least uses the semi-correct "box set" to describe multiple sets);
that disc recordings do not have "grooves," since they only have one
spiral groove; that even the term "record" is sufficiently vague
to verge on inaccuracy (as anyone discussing a discographic database,
or worse yet taking notes on a meeting on that subject, will quickly
discover); that commercial sound recordings haven't involved "wax"
directly since about 1912, or even indirectly since the 1930's...and so on!
However, if I say "set your phonograph speed to 33 and then place the album
on it and lower the arm..." most within hearing (except for the youngsters
who have never seen an analog recording?) will know what I'm talking about.
If I use all accurate terminology, the most likely reaction will be "Huh?!"
Steven C. Barr