by now rock and pop music had become well embedded albeit still frowned upon by the christian elders of the community, but rock music truly burst open to a far more complex and heavier genre as the decade progressed as bands experimented with the new analog synthesizers (and often LSD) while the crooners of the 50's fell out of popularity
the Beatles arriving in America in 1964 totally changed the US music landscape and many American singers became to be seen as too conservative and old school and rapidly lost popularity amongst the youth and would never regain it
illicit drugs, especially LSD became a feature of many rock bands - unfortunately, quite a few of the 60's rock stars would die young from drug overdoses (Brian Jones of Rolling Stones, Jimi Hendrix, Jimmy Morrison of The Doors, and Janis Joplin all died at aged 27yrs, while Marianne Faithful almost died being in a coma for 6 days in 1969) or developed psychoses (Syd Barrett of Pink Floyd), and these deaths, along with other factors would severely adversely impact the free love culture of the hippy movement of the late 60's.
by the mid 1960's the advent of stereo vinyl record technology, and later, stereo FM radio in the early 1970s, encouraged artists to explore with the stereo separation of sound channels while families would start investing in expensive stereo “high fidelity” HiFi systems - previously all consumer music was the same in both ears
in the mid 1960's, electronic music generated by sound generators supplemented with modifications of audio tape recordings were used to create the iconic Doctor Who theme in 1965 and was experimented with extensively by Pink Floyd who often used sounds from everyday objects to create their music - see Dr Who example of early sound generators and tape manipulation:
https://www.youtube.com/watch?v=qsRuhCflRyg
studio recordings were generally done with 4 track tape recorders using 1” tape although by 1968, 8 track tape recorders were being used in the US but had not yet made it to Abbey Road Studios in the UK until c1972
electric versions of 12 string guitars were invented such as the Rickenbacker in 1964 which was played by George Harrison.
guitar and vocal effects machines such as the Binson Echorec allowed for echo reverb effects while the Uni-Vibe in 1968 added swirling chorus and vibrato effects. The Fuzzbox pedal clips the top of teh waveform of the input signal to create a rough, over-driven texture.
by the late 1960s, the portable cassette player allowed music to be taken with you for the first time without resorting to radio, and it allowed easier recording of music and voice than large tape to tape systems which had preceded it, but the audio quality was poor until the early 1970's when Dolby B noise reduction was introduced along with better chromium based tapes
complex analog synthesizers were invented and combined with 8 track audio recording tape and extensively used by bands such as Pink Floyd