Oddly enough, Galactic celebrated its first tour as an instrumental collective by jamming with a pair of high-profile vocalists. A month into their first post-Houseman outing, New Orleans' most popular jamband ambassadors turned their two-night stand at New York's Irving Plaza into a Jazz Fest-style power jam. And, without disrespecting their lost comrade, Galactic confirmed what many already knew: Stanton Moore has always been the group's true frontman.

Though his presence provided Galactic with both a face and sense of New Orleans authenticity, Houseman never altogether gelled with the group's sound. While soul has always been an ingredient in their multi-genre mix, Galactic thrived on meaty grooves, led by drummer Moore's pulsating rhythm. In the past year, Galactic have sharpened their jams, exchanging their long, flowing narratives for compact, layered songs. Broadening their appeal, Galactic is equally comfortable among DJs, hard rock jocks, and hippie-jammers. In many ways, Houseman's sound and style simple constrained Galactic's appeal. On the other hand, Moore, with his empowered geek look and punk-funk playing style, has grown to represent Galactic's three-dimensional personality.

But, just because Galactic parted ways with its singer doesn't mean the group has lost its sense of song structure. Sharpening their jams and buffing up their bass, Galactic have slowly aged into a harder, and much tighter, instrumental unit. Since the release of the Dan "The Automator" Nakamura produced Ruckus, Galactic has embraced its hardcore roots, amplifying Robert Mercurio's bass-lines and focusing on Moore's powerful kick-drum. Ben Ellman has also emerged form the shadows, using his dark horn tone to color the Galactic's underbelly. With Houseman on hiatus since last spring, Galactic have had several months to transition into their current five-piece lineup. So, while this evening's show contained a welcome element of surprise, it also played out like a natural evolution.

While the concept of special guests is anything but foreign to Galactic, this two-night stand generated some rather unusual pre-show buzz. Perhaps a last minute push to help sluggish sales for this Sunday evening show, the group announced that both Soul Coughing vocalist Mike Doughty and Soulive guitarist Eric Krasno would guest at Irving Plaza. With MOFRO's JJ Grey booked as the evening's opening act, even a conservative gambler could confidently wager on a few Grey-asterisks. Thus, fans who attended this Sunday evening show seemed less concerned with who showed up and more interested in how each guest would add to Galactic's transitional sound. Doughty's decision to join Galactic proved intriguing, given the fresh-faced singer's roots in the alt-rock community. Soul Coughing were always among the most organic of their peers, the 1990s alt-rock stars always seemed more comfortable sharing a bill with Everclear and the Black Eyed Peas (as they did on the SnowCore tour a few years back) than on the jamband circuit. Yet, after a well-received appearance at Bonnaroo this summer, Doughty could be the next alt-rock act to embrace jam-nation's open door policy. Offering his college radio hit "Circles," Doughty essentially used Galactic as a backing band, hinting at what the group would have sounded like in a more polished setting. With support spots for Dave Matthews, Counting Crows, and even Live under their belt, Galactic have always flirted with mainstream-rock, a level of comfort any working band has longed for at some point in their career. And, at times, Galactic's sound has pushed towards Matthews' realm, anchored by a powerful, progressive drummer, but narrated by a somewhat out of place singer.

The rest of this evening's guests also each fashioned Galactic in a slightly different context, though, mostly each performer adopted his or her own style to the group's patented blend of jazz and funk. First set, Krasno ripped a few ripe solos during "Snowball" and "Blue Pepper," taking a lead role, while also respecting his guest role and adding to Jeff Raines' textured lines. Likewise, RANA's Scott Metzger, who wondered onstage as if by surprise during "Church," jumped between soloist and band member, favoring Soulive-style funk over RANA's post-Ween rock and ruckus. Metzger, in particular, thrived in this setting, offering a few jazzy solos which maintained the raw, post-punk edict of his band without emulating his trademark RANA tone. Perhaps the evening's funkiest offering featured a trio of well-known drummers: Moore, Eric Bolivar and Joe Russo. One of New York's most prolific players, Russo elicited the evening's loudest response, anchored a three-man drum-jam. Loose, yet inspired, this drum segment amplified Galactic's good-time-funk underbelly, an element of the group's persona which has been relatively hidden since Ruckus' release. With Russo's organ foil Marc Benevento sitting in a night earlier, the drummer's appearance also added a bit of conceptual unity to this two-night stand. Throughout this guest laden segment, ubiquitous jam-scene horn player Cheme, also helped push out Ellman's funkier notes. Well past 1AM, Jen Durkin confirmed growing rumors, appearing for a jam based around "Woman to Woman." Unfortunately, perhaps Durkin's energetic pipes reinforced the statement that Houseman simply never fit into Galactic's well-balanced mix.

If nothing else, Galactic's instrumental fall tour has given the group a chance to assess its place in the jamband community. Known for their guest laden, late night shows, Galactic score high points in the popularity polls, but the group still seems unsure of which musical direction they want to take. At times, Galactic possesses the force and instrumental strength to play as hard as moe., while also retaining the fluidity of a band like Soulive. Perhaps Houseman's departure will also force Galactic to bring its songwriting further into the jam-hop realm, allowing producers to cut and paste their instrumentals into carefully layered compositions. Either way, this Irving Plaza performance proved that a decade in Galactic's career is just starting to take shape.