analog synthesizer (uses analogue circuits to produce sound)
~ Electronic instrument
using analogue circuits and techniques to produce sound electronically, the first types where created in the 1920's with thermionic valves and other electromechanical machineries.
clavioline (electronic keyboard, forerunner to analogue synthesizers)
ondioline (early analogue synth with various sounds and "vibrato" keyboard)
trautonium (monophonic electric instrument from 1930's)