screw ben... Dave & Jerry

does anyone know some of the scales that Dave Glimour and Jerry Garcia might have used.

im really wanting a more psychedelic sound, and know that simplicity can really drive that with a lead wirk, but things tend to get kinda crazy during the "jam solo" part..

what do you guys suggest for a solo that kinda wanders in some keys? i know about tetrachords and the circle of 5ths, so thats alot of help.. does anyone think they may be able to help?

also, ive been told to learn some of their licks and use them in my own work, so does anyone know a song that has a really nice riff that i can work with (floyd or the dead, ill take either)