Jimi Hendrix was the first proper electronic composer... ’cause I think he was the first one who listened to what he was doing. The Marshall guitar amplifier doesn't just get louder when you turn it up. It distorts the sound to produce a whole range of new harmonics, effectively turning a plucked string instrument into a bowed one. A responsible designer might try to overcome this limitation - probably the engineers at Marshall tried too. But that sound became the sound of, among others, Jimi Hendrix. That sound is called electric guitar.