By SANDY MASUO

The Goo Goo Dolls specialize in scruffy, punk-edged guitar pop full of hummable hooks, rock crunch, heartfelt playing and earnest lyrics. And although the Buffalo, N.Y., trio’s first album in four years, “Dizzy Up the Girl,” has an uncomfortably tidy commercial gloss, when the group kicked off its new tour at a sold-out Galaxy Theatre in Santa Ana on Thursday it demonstrated that it hasn’t lost its scrappy appeal.

Supplemented by a second guitarist, a keyboardist and, for one song, a harmonica player, the Goo Goos played a snappy, 90-minute set that crackled with spontaneous energy. The group tackled quieter, moody tunes such as “Black Balloon” as vigorously as sassier numbers.

Despite the quintet’s full sound and lively playing, the Goo Goos actually packed more firepower during the encore, when they played as a trio. Stripped down to basics, the threesome whipped up a more concentrated dynamic. Singer-guitarist John Rzeznik took lots of time out for casual stage banter, and his easy manner and charismatic stage presence enhanced the already warm rapport he and his bandmates shared with the fans.

Openers Athenaeum turned in a set of spunky guitar pop that was just as genial and heartfelt, though ultimately the quartet’s enthusiastic attitude proved more compelling than the songs it played.