On his latest solo venture, the Phish frontman goes avant with a short, playful album that offers knotty reworkings of old compositions. Aside from the gentle Afrobeat rumble of ''Andre the Giant,'' Seis de Mayo's stately orchestral arrangements transcribe Anastasio's guitar-driven rock for the concert hall. It's what the Kronos Quartet might sound like if they played the jam-band circuit.

