Ladies and Gentlemen (Compass, 2016)

The "Ladies" of this album's title are an impressive batch of female guest singers serving as the voice of the Infamous Stringdusters for the space of a song, lending a softer edge to the group's already smooth take on modern string band music. They come from not just bluegrass circles but rock, soul, folk and country, sending each track in a different direction that's still anchored by the instrumental dexterity of the Stringdusters. The band itself takes a back seat throughout to the singers and the songs - content to throw in a run here, a solo there and let the voices of the titular ladies shine.

Some pairings are more successful or interesting than others, a danger of such a laundry list of guest stars on a project such as this. Aiofe O'Donovan smokes "Run to Heaven," a fast-paced bluegrass tune, but Mary Chapin Carpenter's clear tone renders the bluesy "Coming Back To You" in antiseptic fashion. Joan Osborne and Joss Stone fare better with the blues on "Listen" and "Have a Little Faith," respectively, reining in their more bombastic tendencies to fit the occasion.

Sarah Jarosz is stunning on "Won't Be Long," aided by Stringdusters-supplied harmonies and an insistently strummed tempo, and her star turn is echoed in the closing track, a jaunty "Rock and Roll" featuring Abigail Washburn that's the closest thing to a traditional string band number.

The Infamous Stringdusters are perfectly capable of singing their own songs, of course, which is what makes this wide-ranging collection of cameo performances such a fun diversion, though one wonders how practical it will be come tour time. A show featuring all or even some of these singers would be a wonderful evening of music, however, for both ladies and gentlemen alike.