Before the birth of the synthesizer, the only commercially produced instrument that offered a sound that was something more than a glorified organ was the monophonic Clavioline electronic keyboard instrument, which was actually invented by Constant Martin in France in 1947! It consisted of a 3-octave keyboard with 18-22 switches that would alter the timbre of the sound produced through the matching amplifier/speaker unit, and it also added vibrato and other effects.
The concept behind the Clavioline was to produce brass and string sounds that were considered quite sophisticated at the time. Several models were licensed to various global manufacturers, such as Selmer in the UK and Gibson in the USA. Among the most important models were the Standard, the Reverb, and the Concert. The two most famous uses of this instrument were on the 1961 hit song “Runaway” by Del Shannon (Max Crook played the famous solo on that song, using a heavily modified Cavioline) and on the 1962 hit instrumental “Telstar” by the Tornados. Anyone who recalls those songs would instantly recognize the trademark Clavioline sound. John Lennon also used one in 1967 on the Beatles’ hit recording “Baby You’re a Rich Man.”