The 25 digitally remastered cuts on “Le Gran Mamou” range from accordionfiddle duos of the ’20s to Western-style, accordionless string bands of the ’40s. (Accordions came back in the late ’40s and remain indispensable today.) Plus an archaic unaccompanied fiddle duet, and a harmonica solo showing the humbler instrument’s kinship to the accordion. Those used to today’s electrified Cajun sound may miss the bass and drums (or rub-board). Solution: play it louder. The spirit’s the same.

Since “Le Gran Mamou” draws only from RCA recordings, it’s not definitive–just first-rate. Among the best cuts: Columbus Fruge’s African-sounding accordion piece “Saut’Crapaud” (1929), with its defiantly out-of-key vocal; black accordionist Amedee Ardoin’s proto-soul singing on “Les Blues de Voyage” (1934) and Joe Creduer and Albert Babineaux’s “Ma Cherie” (1929), a waltz for accordion and triangle that sounds like a sad, spacey merry-go-round.