By 1971, musicians like Stevie Wonder and Pete Townshend (of The Who) were experimenting with the synthesizer. After the "light rock" sound of Tommy, Townshend was looking for a new direction. Step one was a new guitar and guitar style - playing and sound. Step two was with the synthesizer.
Pete Townshend took the idea of minimalist loops from musician Terry Riley. What happens when you mix a looping synthesizer with power chords?
Now for the bonus round. The second song Townshend wrote with synthesizer loops - Won't Get Fooled Again -
Live at Shepperton Studios, 1978, in front of a very lucky audience. This performance is considered one of the best ever live performances by any rock band. The proof is in the energy.
Years later, synthesizer music became its own genre. Rock music and the synthesizer have never parted ways - bands like Styx, Duran Duran, Chicago and others regular use/used the synthesizer.
And now you know where the guitar and synthesizer first met!