Opting to concentrate mostly on live performance, the New Jersey-based Blue Plate Special have delivered only four albums in their 15 years together. But their bluegrass-, country-, folk-, and swing-influenced music sounds just as compelling on record as it does on stage.

It helps that each member of the quintet ably wears several hats: while Jay Friedman or banjo/guitar player Dan Whitener sings lead on most of the songs on the new Back by Popular Demand, the group’s other members all take turns in the vocal spotlight; and among them, the five play banjo, guitar, fiddle, mandolin, and upright bass. Plus, four of them are songwriters, and this all-originals collection finds them delivering numbers that seem good enough to be old standards.

The diversity is as impressive as the musicianship. Sometimes, such as on Whitener’s “You Can Never Go Home Again,” they sound like Appalachian heirs to traditional bluegrass and country outfits; Jay Friedman’s charming “Rotary Phone,” meanwhile, is a bit redolent of pop vocal groups from the 1940s; Dave Gross’s “Oh Lord I’m Down in a Hole” has gospel roots; and Friedman’s moody “Bed of Roses” reminds me of the seventies work of Dan Hicks and His Hot Licks.