I made a spreadsheet of the audio patents I have on hand. It's a *very*
incomplete list; it includes only the ones I gave out to my
history-of-recording class. I was limited by time (1 semester) and
You can get the spreadsheet here:
If it seems heavy on microphone patents, that's because we did a long
unit on the history of microphones. Since these were students in the
recording program, mics are something they use all the time, so there
was a lot of curiosity.
One interesting gap: Apparently CBS chose not to apply for a patent on
the long playing record. The patent number that shows up for Peter
Goldmark and the LP is actually a later one (applied 1952), a stereo
disc with one channel on either side of the disc, and a cartridge
assembly that played both sides at once.
I included Blumlein's 1931 patent on stereo, snd Western Electric's
patent on the 45/45 groove, filed only five years later. Interesting
factoid: Blumlein worked for the British branch of Western Electric
(which became STC) before jumping to UK Columbia (which became EMI).
Further neat factoid: the attorney who signed Edison's original patent
application for the phonograph was none other than Samuel Insull, future
utility magnate and crook.
What I don't have: patents on digital audio recording and optical discs
-- there just wasn't time, and I didn't want to step on the toes of the
guy who teaches digital audio.