^egg is awesome, you would like their earlier incarnation with Steve hillage, arzachel. Also the nice is cool
I just don't consider the grateful dead psychedelic. They don't use any trippy sounds at all. They are just a folk band.
Which goes to show that good psychedelic music doesn't need trippy sounds. Good psychedelic music will fuck with your brain with it's sheer musical composition. I would have to say using a bunch of effects is the "easy way out" when it comes to psychedelic music. Anybody can plug effects into their instruments these days and deem themselves a psychedelic band.
I can make a psychedelic song with just an acoustic guitar, people tell me my music is trippy all of the time. What is even more psychedelic is if I multi-track and experiment with overlapping time signatures etc. With my psychedelic music, I like for it to have dense layers which flow smoothly with each other and give you that dank feeling. But if you have too much going on it will just sound murky.
If you think that Grateful Dead is "just a folk band" then you have some serious listening to do. They are some of the pioneers of psychedelic music.
If you learn more about music and then realize what's going on in a Grateful Dead song, they are definitely psychedelic. Sure a lot of their music is based around country, folk, blues, and rock, but The Dead have learned to combine all of those genres into one psychedelic mass, especially in their live performances.
To me there is nothing more psychedelic than a live 10 minute Dead jam; you can feel the synergy between them when they improvise, and once you start to learn music theory, you start to hear music differently, at least in my experience.
Saying that Grateful Dead isn't Psychedelic seems a little absurd to me. Why do you think most of their followers are acid trippers? Why is it that when you go to a Grateful Dead show it's practically raining LSD?
Listen to the song "China Cat Sunflower" off the album "Europe '72".