The surviving members of the Grateful Dead.

The Dead
7:30 p.m., April 26, XL Center, 1 Civic Center Plaza, Hartford, (860) 249-6333, xlcenter.com

Do most Deadheads know Mickey Hart was a world champion rudimentary drummer, winner of the first World Music Grammy, author of two books on the history of percussion and a regular hand-lender at the Library of Congress, preserving and digitizing indigenous music? Hart, now 65, toured with the true Americana music ensemble, the Grateful Dead, for 25 years. He's performed with Planet Drum, Mystery Box, and various musical incarnations post-Garcia. He's been a lifelong student of rhythm while relentlessly searching for the sound. His music path would have been different had he not met his future drum brother, Bill Kreutzmann (the Dead's other drummer), in 1967. The music of Janis Joplin later that night helped put his music in perspective, and the rest is history.

I had met Hart at a lecture in Manhattan in 1998, so I was happy to catch up with him for a pre-tour chat.

Over the decades, Hart played thousands of concerts, but no set list was ever duplicated. Is there a favorite song in there somewhere? "The Pump Song"?

"Wow," said a surprised Hart. "That's a good question; there's lots of great ones — 'Attics,' 'Stella [Blue]' — that stop your heart when played beautifully in depth. Then there's the chords, rhythm and word combos. I don't know."

Watching him play percussion, his style is purely singular and non-traditional.

"My playing has to have a sense of groove; a license for unusual flights of fancy that pollinate other things while maintaining a groove between time and song," said Hart. "It's more fluid as I get older and I get more versatile in quick changes."

Hart's an electronic wizard who built a digital encyclopedic universe of sounds called RAMU (Random Access Musical Universe) that he's bringing on tour. "We have lots of surprises. RAMU will be there and it'll be spinning out incredible universal sounds."

Beyond the surprises generated by RAMU, fans can reasonably expect some surprises in the song structures and in the set list as well.

"Well ... 'King Solomon's Marbles' [a rare track off of 1975's Blues For Allah] — we might do that. Maybe make some magic and play well. The song is the trip; we know them inside and out, but it's how you get there, in between and back that creates the magic. [We're playing] long jams in rehearsals as opposed to just the songs and concentrating on playing; learning the rhythm instead of the songs. Everyone will be very surprised. This is the best configuration we've ever had," said Hart.

Hart is known for his interest in preserving indigenous world music. He started the Endangered Music Fund to save ancient rhythms, pressed into action by the Amazon's destruction. "The rainforest is where people had their musics. Their environment was torn and their music was endangered, so I used my role at the Folklife Center to record the music of endangered global cultures, and released six of them."

Speaking of endangered music: He discovered an old tape in the late '60s of the Gyuto monks, the last surviving singers to leave Lhasa after the 1959 Chinese invasion. Through his advocacy, he recreated a fuller sounding choir for release and one monk, Nawang Khechog, was nominated for a Grammy in 2001.

"Would you believe Gyuto [Chants for Peace] is number 10 on [World Music] Billboard right now? I just checked before calling you. I don't believe it; I charted them," said Hart.

Hart once testified on Capitol Hill for advanced music therapy funding. Twenty years ago, his grandmother, in Alzheimer's advanced stages, hadn't spoken for a year. He drummed by her hospital bed and she woke up and spoke his name.

"The brain is being mapped and we're now on the verge of being able to see how brain waves react, before, during and after an auditory trance," said Hart. "Beth-Abraham [Hospital] in the Bronx is making strides in brain-rate processing. When this is validated in the public's eyes, then doctors can prescribe music therapy as preventative medication. Life-enhancement tools, drum circles."

What's Hart's favorite rhythm?

"Earth. Big Bang, radio waves; we are embedded in a universe of vibration. There's no sound out there; it's all wave forms. We change it into sound. It's washing all over us from 20 billion years ago, so the earth sings. We've measured it as a low B-flat with a low-end frequency of 57 octaves below middle C. It's better to be in sync with nature," he said. "Resonate and be together. It's Christian Huggins 'Entrainment Theory'; dating back to Pythagoras ... all mathematics. The Law of Octaves, the science of music. ... Does that answer your question?"

Do you feel there's a separation in music tastes between inner cities and suburbia?

"There has to be a reason that serves a function in the community; people talking about real things that affect them in a way that's meaningful," said Hart. "If the community buys it, it must want it. Every community needs music and vice versa. None can exist without the other. You can't make music without a community."

Click here for Dave Bonan's Q&A with Mickey Hart.