Grateful Dead: Anthem Of The Sun (1968)
My response might have been different if the local public library, my source of new music back in the days before my allowance accommodated actual record purchases, had stocked 1968's Anthem of the Sun rather than the basic greatest hits collection. Because of all their "studio" albums (more on that in a second), Anthem is indisputably the most psychedelic and sonically adventurous, much more in line with the weirdness I'd hoped to find when I first checked them out. (1969s Live Dead, not to mention pretty much any of their archived shows from their pre-70s psychedelic period, would have done the same, but I didn't have access to those at the time, either.)
Anthem is an interesting recording, a hybrid weaving together studio and live recordings, resulting in a blissfully disorienting mix that at times has the pristine aesthetic of a studio recording while at other times devolving into a chaotic, layered blend of multiple live performances. Even aside from the sound, the songs (at least on side one) are much more deliberately "psychedelic" than on the more garage-rock-sounding, amphetamine-paced debut from a year prior. "That's It For The Other One" is a multi-part suite, bookended by a melodic Jerry Garcia-helmed ballad with a rollicking Bob Weir rocker tucked into the middle, a striking piece that was a reliable live showstopper right up until the end (though after a few years they largely dropped the Garcia sections, while elongated the Weir section into a jam-friendly monster). The song dissipates into a haze of feedback, with another extended piece, "New Potato Caboose," emerging from the din; it, too, is a trippy, drugged out opus (though, sadly, one that only endured for a couple years in the live repertoire). The album side closes with the pithy, almost poppy Weir number "Born Cross-Eyed," a chaotic slash-and-burn head trip (and the song that, according to legend, led to the label-supplied producer storming out of the sessions when Weir demanded he capture the sound of "thick air").
The vinyl's second side has only two songs, both fronted by the band's resident bluesman Pigpen: "Alligator" is a fairly straightforward blues-rock tune, a nifty riff followed by one of the better jams captured on a studio (ish) Dead album); "Caution" is a Pigpen vocal vamp seguing into an extended feedback workout, definitely diehards only (though displaying the band's more free-form, often underappreciated sonic experimentation).
The album was reissued in 1972 with a slightly altered mix. Unlike the follow-up album, 1969's Aoxomoxoa, which similarly circulated in two different mixes, I find the differences here to be more subtle, though I prefer the slightly messier and more chaotic original version. A recent anniversary edition included both mixes, so you can obsessively cross-reference to your heart's delight.
Here's some footage from a 1968 show, with a live jam into "That's It For The Other One":...and a video clip for "New Potato Caboose":