Furthur earlier this year – photo by Norman Sands

About halfway through the second set of Furthur’s show at Jones Beach Theater, the band segued into a pitch-black version of “Dark Star.”

The vintage Grateful Dead tune, a valentine to musical improvisation, has fast become a staple in Furthur’s ever-growing repertoire. However, this venture into spatial exploration – rather than being up-tempo and melodic – was especially dissonant, as the band indiscriminately clawed its way through the stratosphere.

Following the first verse of “Dark Star,” the music ground to a virtual halt. Shifting into jazz mode, the band members then went off in their own musical directions.

Bassist Phil Lesh dropped soft, yet steady notes while guitarist Bobby Weir delivered short, choppy rhythms (as is Bobby’s tendency). Keyboardist Jeff Chimenti playfully chased the chord progression staked out by lead guitarist John Kadlecik. Indeed, throughout the show Kadlecik delivered terrific leads, with a keen sense of economy. The band coalesced beautifully for the second verse of “Dark Star.”

“Dark Star,” was preceded by a muddy treatment of “He’s Gone,” which was followed by a furious jam with multiple layers. After teasing the crowd with what could have been a powerful launch into “The Other One,” the band once again shifted gears and glided into “Dark Star.”

The jamming displayed during the top of the second set had all of the sonic earmarks of what the late Jerry Garcia, spiritual Godfather to Furthur, used to refer to as, “weirdness, weirdness, weirdness.” While some members of the crowd seemed nonplussed by it all, for others it was quintessential Grateful-Dead music: mysterious, adventurous, reckless and, yes, weird.

Yet, along with a thunderous “Shakedown Street” to close the first set, the “He’s Gone”/Jam/”Dark Star” triplet was the highlight of an otherwise uneven outing.

The show opened well enough, with a fiery “Samson and Delilah” (Bobby on tambourine) into Traffic’s “Dear Mr. Fantasy.” But there was very little jamming throughout the first set, which was lumped together by fairly lackadaisical versions of Bob Dylan’s “Just Like Tom Thumb’s Blues,” “Jack-A-Roe” and “Brown-Eyed Women.” What’s more, the song selection left few opportunities to hear the generally rich harmonies delivered by backup vocalists Sunshine Becker and Jeff Pehrson, who spent most of the set offstage.

A decent chunk of the second set was devoted to a somewhat listless wedding of “Weather Report Suite Prelude/Part 1” into “Let it Grow,” along with admirable if standard versions of “Unbroken Chain” and “The Wheel.” The show closed with a pedestrian, albeit rousing cover of The Rascals’ “Good Lovin.’”

Perhaps it was the venue. Jones Beach Theater, while scenic, doesn’t allow for much enclosure for the acoustics. The sound(s) often feels diluted and drowned out by the wind ripping through the bay that is in the back of the stage. Perhaps it was because Furthur was performing for the third night in a row in as many locales – a schedule that could be taxing for Lesh (71) and Weir (63), who, of course, have been on the road for the bulk of their lives.

I mentioned to a buddy of mine who had attended Furthur’s show the previous evening in Bethel, NY, that, despite said musical nuggets, the band didn’t really catch the flame at Jones Beach, and that the show was not as gutsy as the nearly dozen shows I’ve seen since the group’s formation in late 2009.

He gave me a knowing smile. As it was with the Grateful Dead, who had its share of clunkers, it’s safer to see every Furthur show (or as most as humanely possible) than to leave yourself to chance.