At his core, Frank Zappa was a composer. As well, he was a humorist whose lyrical sensibilities ranged from satirical and silly to profane and absurd. He was also a fantastic guitar player. Still, when looking at his work, it begins and ends with hundreds of songs that within many contain arrangements written largely for rock musicians that were as challenging and inventive as any scored for a symphony. In recognition of its 40th anniversary Zappa’s son Dweezil and his Zappa Plays Zappa band have taken on the task of performing in its entirety the Roxy and Elsewhere album, bringing the tour on this February night to Downtown Disneyland’s House of Blues.

From the first notes of “Filthy Habits” it was obvious that the personnel new to the Zappa Plays Zappa band, one that has hosted several former members of Frank’s groups throughout its various incarnations, were more than capable of presenting the repertoire faithfully. Longtime saxophonist Scheila Gonzalez and fresh face Ben Thomas, whose duties included trombone, trumpet, guitar, and vocals, doubled shearing horn lines against Zappa’s viciously dark melody before the dexterous and dangerous syncopated demands of the instrumental gave way to improvised bliss backed by the thunderous and nimble Ryan Brown on drums. Reassuring the near-capacity audience, most of whom greying fans from Frank’s days, the ensemble navigated every curve finishing to validating approval.

Introducing the concert’s centerpiece as a record that while 40 years-old still sounds like it’s from the future, Dweezil led the band through the 10-song double album in sequence, opening with “Penguin in Bondage,” and the first real test of Thomas’ fitness for the various vocal stylings Frank employed on the original and in concert. In a way, the choice to perform in character, so to speak, walked the eyelash-thin line between impressive and impression, with Thomas achieving the former. It’s a choice Zappa Plays Zappa has to make each and every time onstage, delicate in avoiding a slip into the realm of tribute act. Rather this unit should be likened to an orchestra playing The Rite of Spring, as by comparison it would be exceedingly ill-informed to refer to a philharmonic as a mere Stravinsky cover band.

The daunting heft of Zappa’s compositions requires a level of aptitude and precision balanced in flair and feel, and this band carried it off in sparkling fashion. Anchored by the polyphony of keyboardist Chris Norton, the Roxy set roared and rocked, slinked and swung, providing showcases for each musician but none more than for Dweezil’s increasingly virtuosic guitar. Solos varied in scope and speed, exploring modal depths with patience, garnering the loudest and most sustained reactions in the show’s second half. On a series of Zappa favorites including “Florentine Pogen,” “The Black Page #1 & #2” and encore “Zomby Woof,” which featured guest guitarist James Santiago and Zappa going toe-to-toe, the group gave heavy credence to a notion that these are some of the best players on the planet.

Frank Zappa demanded the near-impossible of his bands, even writing pieces he swore could not be accurately presented by human beings. Accepting the responsibility implied in performing his work is, in and of itself, as bold and daring as it is commendable. Zappa Plays Zappa is just that bold, just that daring, just that commendable, and the Roxy and Elsewhere tour, just that remarkable.