The Theremin.

this is so much harder than it looks… I reluctantly returned mine to Moog after I completed volume 1 of suffering cat noises

The Kingdom by @SolarHeavy

Google AI "The theremin is an electronic musical instrument invented by Leon Theremin in 1920, unique in that it's played without physical contact, by manipulating electromagnetic fields around two antennas to control pitch and volume"

ronnie montrose had a custom job on his geetar

Good Vibrations!!!

interesting technique

It’s a cool instrument that is so simple to play but hard to master. The right hand controls pitch while the left controls volume.

I remember this during my sound weapon deep dives.

Cool

The band Thank You Scientist (possibly now defunct) uses a Theremin during the 25 second intro to their song "Wrinkle" if anyone is interested in implementation of the instrument as not the feature but a component. And also at 3:57 in the following tune: