Come to think of it, "Cambrian" isn't the best qualifer since there wasn't an explosion of species (genres), but of records in a few popular genres. Let's just say "explosion".
This didn't happen just because music was "cheaper and easier". It happened because of the youth culture of the 60s and the asteroidal impact of rock and roll (better science metaphor?), especially the British Invasion of 1963-64. Kids started bands because it was cool. Most weren't expecting to make money or become stars. They were in it to imitate their heroes and impress girls. This history is well known to fans and students of the period, and it's documented. Fanatical pop archivists have traveled to places like Kansas City and tracked down members of bands who pressed 300 copies of some 45 they recorded in 1966 and interviewed them about it.
By 1969, there was a sharp dropoff, not because the economics changed (it's not as if electric guitars got more expensive) but because the cultural moment had passed. Rock and roll became "rock" and started taking itself seriously. Bands started putting out slicker stuff that, in retrospect, was far less fresh and exciting. Fans of rock and roll talk about those years as the dark ages. The DIY aesthetic kicks back in bigtime with punk, which was a conscious effort to revive the values of the mid-60s (https://www.youtube.com/watch?v=UHPQI4b0ybE#t=18).
As I said, this stuff is all well documented. I learned about it from old fanzines and liner notes, so I don't have websites handy, but it ought to be pretty easy to find out about.
This didn't happen just because music was "cheaper and easier". It happened because of the youth culture of the 60s and the asteroidal impact of rock and roll (better science metaphor?), especially the British Invasion of 1963-64. Kids started bands because it was cool. Most weren't expecting to make money or become stars. They were in it to imitate their heroes and impress girls. This history is well known to fans and students of the period, and it's documented. Fanatical pop archivists have traveled to places like Kansas City and tracked down members of bands who pressed 300 copies of some 45 they recorded in 1966 and interviewed them about it.
By 1969, there was a sharp dropoff, not because the economics changed (it's not as if electric guitars got more expensive) but because the cultural moment had passed. Rock and roll became "rock" and started taking itself seriously. Bands started putting out slicker stuff that, in retrospect, was far less fresh and exciting. Fans of rock and roll talk about those years as the dark ages. The DIY aesthetic kicks back in bigtime with punk, which was a conscious effort to revive the values of the mid-60s (https://www.youtube.com/watch?v=UHPQI4b0ybE#t=18).
As I said, this stuff is all well documented. I learned about it from old fanzines and liner notes, so I don't have websites handy, but it ought to be pretty easy to find out about.