[don ward]

Humble correction to this premise;
33 1/3 has been a recording standard for over 75 years long before the
lp was ever developed.
Original movie sound was recorded on a 16" disc playing at 33 1/3, not
recorded on the film. I have several of these early sound movie sound
discs in my collection.
Radio stations had programs supplied at 33 1/3 on 16" discs from the
late 20s through the late 40s.
There were many companies producing daily and weekly programs for
distribution across the country. Many of these were 15 minute programs
other producers specialized in music for radio stations, usually 6-8
cuts per side.
Just as early electrical 78s had a basic recording curve so did the
transcriptions. Most did not require any treble roll off they did
require bass boost.
RCA was about the first to introduce a recording curve with treble
roll off with their "Orthocoustic" recording process to reduce surface
noise on play back by reducing the hi end. The Next curve was
developed by National Association of Broadcasters in the 40s, this was
the NAB curve which as it turns out is very close to RIAA curve used
by modern LPs.
16" discs for radio were never recorded at 78rpm.


** Most 16 inch discs are 33.3 rpm

Actually, 16" disks were in use long before 33 1/3 RPM was a common
speed. Their main feature was that, at 78 RPM, an entire fifteen-minute
radio show could be placed on one disk. That's the way radio shows were
distributed for many years.

Isaac