My favourite psychedelic (ROCK, not electronic) albums: great in "normal" conditions, even better in altered states of mind. I tried to give the list some sort of order, but it is not so important since they're all excellent.
(Remember: it is a subjective list)
This band always manages to take the exact psychedelic perceptions experienced under the influence of mind-altering substances, directly transposing them into music. A little depressing here and there, but still a great trip.
Recommendations:
Os Mutantes - Os Mutantes
The United States of America - The United States of America
Red Krayola - The Parable of Arable Land
The Mothers of Invention - We're Only in It for the Money
I love 3 and 5, and 14 is one of my favorite albums of all time
I know both red krayola and frank zappa, but I consider their works to be more experimental than psychedelic, and for me they're not particularly suitable for a psychedelic experience (especially zappa, even because he was against any sort of drug use :P); but I'm going to listen to os mutantes and usa, thank you!