The group heard on "The Velvet Underground Live, 1969" is a jam band. So are Pink Floyd or German psychedelic art-rockers Can, the early Stooges or freak-folk legends the Fugs. There's a little bit of all of these groups in the New York quartet Animal Collective, but hardly any Grateful Dead.

"We never really strived to be the most accomplished musicians in terms of technical stuff like guitar solos," says bandleader Avey Tare, aka Dave Portner. "A lot of times you hear the words 'jam bands' and you think Phish or something like that, because they tend to jam, and when you say 'jam,' it means 'rock out.' We would never want to do anything like that, but at the same time, it's kind of like, 'Well, how can you do something like that with sound?'

"We were really into Pink Floyd when we were younger in high school -- we were just inspired by how they could not worry about playing the instruments so much, but would improvise large portions of their sets. I think just because we like writing songs and melodies so much, we reached a point in 2000 or 2001 where we improvised a lot over long periods of time together, just sitting in our apartments and making stuff up on the spot. But at the same time, we were thinking, 'How can we incorporate more of a song structure in this so we won't always have to rely on improvisation?' It's hard a lot of times to just go onstage and improvise a good set."

On its sixth and seventh albums, 2004's "Sung Tongs" and 2005's "Feels," both released on the independent Fat Cat Records label, Animal Collective wound up with a striking sound that is loose, freaky, psychedelic and often very free-form and experimental. At the same time, songs such as "Did You See the Words," "Flesh Canoe" and "The Purple Bottle" are full of effervescent pop hooks, bringing to mind ork-pop peers like the Arcade Fire and the Decemberists, or the Elephant 6 bands (Apples in Stereo, Neutral Milk Hotel and the Olivia Tremor Control) of the mid-'90s.

Avey Tare/Portner and his fancifully named bandmates Panda Bear (Noah Lennox), Geologist (Brian Weitz) and Deakin (Josh Dibb) are high school friends who met in Baltimore and casually played music together in various combinations as they scattered to attend college in different cities.

"We never had a serious band until we all came to New York in 2000," Portner says. His first D.I.Y. recording, 2000's "Spirit They're Gone, Spirit They've Vanished," was just him and Panda Bear, but the others soon joined in for a series of prolific releases.

"When we started making records, I didn't think anybody currently was making anything as good as [Pink Floyd's] 'The Piper at the Gates of Dawn,'" Portner says. "When Noah and I made 'Spirit They're Gone, Spirit They've Vanished,' I just wanted to make a record that sounded like that, but also sounded very current -- like what was happening today, instead of us trying to make a '60s psychedelic record.

"Now I think we're trying to work with what we have to make new and interesting sounds, and hopefully people who are into psychedelic music or whatever appreciate what we're doing. ... For us, it's all about some sort of natural progression forward, and just feeling like we're going to new places."

Recent touring has found Animal Collective benefitting from a growing indie buzz, and the excitement is fueled by the fact that its last two albums have been its strongest.

"Every record to us is kind of like its own individual project," Portner says. "Sometimes I feel like I'm more influenced by films in that way, like how a director's film seems like its own statement, and you don't really think about it as related to the last film that he or she made, even though there might be some similarities between the two.

"For 'Feels,' it was just a good time for all four of us to work together again, because it had been really difficult the last time because of the time and place in our lives. We didn't have much money, and we were balancing work and writing songs and trying to get together to play and work on stuff. ... Now, it feels really good to play the 'Feels' and 'Sung Tongs' stuff live, because it takes on a completely new feeling."

Which brings us back to jamming.

"We never want to be slaves to a set list, where we feel like we can only be happy if we get up and play everything like we planned to," Portner says. "We don't want to be this band that gets up there and repeats the same thing over and over again every night, so every night we play something different. We'll make a list before we go out onstage, but we're always up for 'whatever happens, happens.'"

Dig it, man.

REASONS FOR LIVING

The indie-rock scene loves to coin new subgenres, and you may see Animal Collective and kindred spirits such as Devendra Banhart called "freak folk." But there's a long tradition of uniquely twisted psychedelic folk-rock, and here are some of my favorite examples.

The Fugs First Album and The Fugs Second Album (Fantasy): Beatnik poets from the Lower East Side drop acid and wax poetic/scatological on tunes such as "Slum Goddess," "Swinburne Stomp," "Frenzy" and "Group Grope," all famously recorded during one long bacchanal/jam session in 1965.

The Best of the Incredible String Band, 1966-1970 (Warner Special Marketing): By far the strangest and most unjustly forgotten artists to perform at Woodstock, the Incredible String Band mixed the ancient mysteries of Celtic folk music with the new discoveries of psychedelia for a slippery and seductive sound on albums such as "The Hangman's Beautiful Daughter" and "The 5000 Spirits or the Layers of the Onion," which are well represented here.