After playing musical chairs with lead singers over the past few years, it makes perfect sense that the members of Galactic have made their most vocals-oriented album with Into the Deep. Eight different singers appear over these 11 tracks, and it’s the first Galactic album that’s all about the songwriting, rather than the grooves or the jams.

The bad news first: Those eight singers largely don’t include the ones who’ve been most visible with the band over the past year: Maggie Koerner, Erica Falls and Cyril Neville (Koerner is here as co-lead singer of “Dolla Diva,” first released online a year ago and a live staple ever since. The other two are MIA). To these ears, the two women in particular were perfect fits for the band—witness the jump in energy level when Falls joined them onstage at Jazz Fest this year—and it’s a bit perverse not to find them here.

The good news is that a fine batch of material is well served by the singers present. The lyrical wisdom and Stax sound of “Does It Really Make a Difference” are worthy of its singer, Mavis Staples. While Macy Grey overstayed her welcome at Jazz Fest, she’s perfect for the slow-burn of the title track, which gets an uncharacteristically Motown-ish production. And there are a few funk/rap hybrids, the best of which features 2013 Jazz Fest sensation Brushy One-String. Even the closing instrumental “Today’s Blues” is a fine bit of gospel featuring a Rich Vogel B-3 solo straight from the church, quoting Curtis Mayfield’s “Amen” just as it ends.

With so many singers and styles at play, Into the Deep is bound to sound a bit like a compilation album—and as usual on Galactic studio albums, there aren’t many moments of straight-up band chemistry (guitarist Jeff Raines is practically invisible), though there’s more live playing and less computerization than on their last few. If nothing else, it gives them some good fuel for their next round of changes.