I will say something about this incredible electronic duo from New York -
SILVER APPLES, since they're not mentioned. They had a psychedelic and cosmic feel to their sound, so I think they fit in this thread even though their approach to pop song was unconventional. Their use of a primitive synthesizer and a drum created some pretty unusual music for that time foreshadowing electronic music of Kraftwerk and Suicide especially, since they, like Silver Apples, operated within rock idioms. Well, maybe that's what Suicide would've sounded like if they made music in the late 60's.
But, that minimal and repetitive approach to a pop structure, with an incredibly catchy driving beat, was very fresh and innovative. Although we're now very well used to this idioms of electronic music, it doesn't take away from the freshness of their sound and this music somehow doesn't feel dated. At least, not for me.
They released two albums in the late 60's:
Silver Apples (1968) and
Contact (1969), which were re-released in the mid 90's when the band briefly reunited. I have both of this albums on one CD so I used to always listen to them together.
Silver Apples (1968) - I can say that the first album is more psychedelic and spacey, there's more use of oscillators creating audio signals that feel like they're coming from outer space. My personal favorites are: Oscillations, Seagreen Serenades, Program and the incredible Misty Mountain that closes the album.
Contact (1969) is slightly more rocky and direct. That is especially evident in the lyrics which are not cosmic and abstract like in the first album, but more concrete, personal and emotional. I especially like: Ruby (with a catchy country rhythm), Gypsy Love, You're Not Foolin' Me and the wonderfully hypnotic A Pox On You.
Here are some examples from both albums:
"Oscillations" and "Seagreen Serenades" from Silver Apples (1968)
"Misty Mountain"
"You and I" from Contact