Nickel Creek thrives on contrasts and contradictions.

It’s not enough that the bluegrass trio (whose members are all in their 20s) is breaking new ground in a musical genre stereotypically reserved for old-timers.

Consider these aspects of the band’s live show Wednesday at Liberty Hall:

• A hoedown instrumental piece suddenly burst into Nirvana’s angst-ridden “Lithium.” Later, a touching new tune — a plea to God for direction in life — was followed up by Beck’s “Where It’s At.”
• Throughout the show, Chris Thile jumped around on stage like a rock star. Only he plays the mandolin, not an electric guitar.
• Thile “flashed metal” — the devil-horn salute usually reserved for rock concerts — at bassist Mark Schatz as Schatz clogged.

It had been just five months since Nickel Creek performed in Lawrence, and the group had appeared in Kansas City a few months earlier. But a sizable crowd still packed Liberty Hall Wednesday.

The trio relied on re-tooled harmonies and super-fast versions of songs to mix up its standard live tunes. “When You Come Back Down” and a stripped-down version of “The Lighthouse’s Tale” especially showcased the band’s vocal skills, while several blazing instrumental numbers featured Thile on mandolin, Sara Watkins on fiddle and Sean Watkins on guitar.

The San Diego group tested plenty of new songs on the audience, and the new material seemed as solid as its first two albums, including the latest one that came out in 2002.

Hopefully, Nickel Creek will return to the recording studio soon. Otherwise, it might take another album for the ensemble to pack Liberty Hall again, especially if it returns soon.

Then again, the band seems to keep its shows lively, despite a rigorous touring schedule. And the Lawrence appetite for acoustic music — especially solid acoustic music that’s quirky enough to incorporate Nirvana and Beck — only seems to be growing.