The problem with power pop, which the Elevators played in their Cellar Door debut last night, is that when it's good, it's very, very good, and when it's bad it's just about insufferable.

The Elevators, a quintet from Massachusetts, at least have the technical acumen to render their weak material with considerable enthusiasm and energy. That 90 percent of their songs seem punched out from a singularly constrained mold doesn't help much. Neither do the group's frequent power pop poses which by now have started to wear thin.

At their select best moments -- "Don't Let Me Die" and "Stick-ball Kids" in particular -- the Elevators succeed in slowing down the frenetic pace a bit and inserting some melodic guitar lines and a few clever changes. Then, they come across the Graham Parker watered down through Thin Lizzy, a pleasant derivation.

With lyrics lost in an unbalanced sound mix, the Elevators had to let the music stand on its own. It was weakkneed. If the group finds a distinct voice -- the chops they have well under control -- they might well live up to their name. For now, the dead weight of stylistic impasse is keeping the door open. The Elevators are stuck on ground floor.