The Leo Kottke/Mike Gordon show at the Barrymore Tuesday had the unexpected effect of uniting generations.

In an unlikely twist of fate, hippies and grandparents came together for a night of great music, as the cross-generational appeal of the duo drew an audience of all ages. This was all done in support of their tour of the new album Sixty Six Steps. While the variety of fans didn't exactly join hands and sing along, everyone had a good time, though the concert was shorter than expected.

Signs posted all over the lobby warned the audience to keep crowd noise to a minimum during the sit-down concert, an unusual occurrence at the grungy Barrymore.

The concert got off to a slightly awkward start, with half the audience ready to dance and the other half enjoying the subdued mood. These two forces kept an uneasy balance throughout the show, with the hush of the crowd occasionally punctuated by whoops and yells of encouragement.

Kottke and Gordon seemed stiff at first, as well. Both looked road-weary and tired. With a minimum of fanfare, the two entered to ample applause and plugged in. Then, facing each other, they slipped into the old Kottke tune "William Powell."

They kept this pose throughout the show, just two guys, two microphones, an acoustic guitar and acoustic bass. There was no backdrop or stage decoration, and the lighting effects were kept to a bare minimum. The stripped-down minimalism matched the music well. Audience members felt like they were watching Kottke and Gordon jam in their basement.

Once the duo got warmed up, things started to flow. The second tune was an upbeat "From Pizza Towers To Defeat," followed by a majestic reworking of the Kottke tune "Ojo" from his 1969 debut album.

The night featured several reworked Kottke tunes, with Gordon adding in pitch-perfect bass parts that sounded like they'd been there all along. To the audience's surprise, the pair didn't focus on Sixty Six Steps, playing more covers and older tunes. One guy up front even held a sign requesting the song "Can't Hang" off the new album, but Kottke and Gordon didn't play the obvious crowd-pleaser.

It was just as well, since the older songs felt more settled and relaxed. Both musicians forgot a lyric on a different newer tune, and Kottke later joked that he keeps "rearranging Mike's songs without telling him."

Musically, the balance was off on some songs, with Gordon's bass overshadowing the guitar. Both played well, but the audience sometimes couldn't hear Kottke as well as it would have liked.

Once they fell into the groove, it didn't matter — there was no stopping the music. Kottke and Gordon melded effortlessly into a rhythmic folk machine, making up for the lack of a drummer.

Kottke stayed on the six-string guitar for most of the concert, but the energy definitely kicked up a notch when he got out the 12-string to play the Sixty Six Steps cover of Pete Seeger's "Living In The Country." Gordon did his part by bringing the song to a close with a thumping bass solo that elicited cheers from the audience.

The audience responded to the music throughout the concert, especially during pauses between songs. You could tell each musician had his own fan group when the cheer "We love you Mike!" was followed by a "We love you Leo!" from a different part of the crowd. To conclude, another audience member shouted, "We love both of you!"

Kottke engaged in his customary crowd banter and weird humor right off the bat, introducing the act by saying, "I'm Bob Cratchit, and this is Mike Gordon." Kottke's odd digressions touched on everything from finding hair on microphones to the injustices of guitar tuning.

Gordon didn't talk much to the crowd at first, but was eventually forced to when Kottke broke a string and had to replace it. At first, the awkward silence was broken by another shout of "I love you Mike." Gordon responded pitch-perfectly, waiting a few seconds before whispering "Me too" and cracking up the audience.

Gordon then took the opportunity to wax lethargic about his former band Phish, accompanying the tale of the "band-versus-audience chess game of 1992" with an unusual descending bass line.

Kottke and Gordon ended the show a little over an hour after it started, disappointing any seasoned Gordon fans in the audience, who would expect at least an hour more. The final tune was "Disco" off the duo's 2002 release Clone.

The audience immediately stood up and demanded an encore. When Kottke and Gordon came out, the audience remained standing in front, throwing glow sticks in the air.

Kottke was hit with a glow stick while walking off a second time, but he didn't seem to mind. That's because Gordon and Kottke's music has an uplifting effect on everyone present — including the performers, who started out stiff and tired but livened up later. Though the show clocked in at a measly hour and a half, old and young alike left feeling relaxed and content.