The theremin is a strange early 20th Century electronic musical instrument. Its pitch is determined by the proximity of a hand to one sensor. Its volume is determined by the proximity of another hand to another sensor. Its sound is rather spooky – the theremin is frequently heard in horror films.

The Ondes Martenot (pronounced rather like “Owned Martenoh”) has a sound similar to a theremin, and I’ve always assumed that the two were very similar instruments – possibly just made by different companies.

But today I learned that the Ondes Martenot has a keyboard.

Theremin:
https://en.m.wikipedia.org/wiki/Theremin

Ondes Martenot:
https://en.m.wikipedia.org/wiki/Ondes_Martenot

Some theremin music:
https://youtu.be/nE_sAnSkW-Q

Some Ondes Martenot music:
https://youtu.be/v0aflcF0-ys

Jeez. I’m surprised that nobody here found this thread worthy of a comment. Both the Theremin and Ondes Martenot are very interesting musical instruments.

And my two YouTube links have some music that’s interesting, at the least.

This is a video that I found that I think is perfect for showing someone the things that can be done with this instrument. Far more versatile as a musical instrument than a Theremin in my view. But the artist seems to make all the difference. As goes John Lennon's Quote:
"I'm an artist, you give me a fucking tuba, I'll get something out of it."




Link to original video: https://youtu.be/Yy9UBjrUjwo

Huh, learn something new every day. Very cool sounds are possible, one could make his own movie score...zombie movie came to mind