Few record labels better encapsulated a scene, a sound and a city than Philadelphia International. The imprint, founded in 1971 by writer-producers Kenneth Gamble and Leon Huff with oft-overlooked third partner Thom Bell, served as a clearinghouse of sorts for the Gamble-Huff compositions that defined Philly soul music.

Ir was an all-in venture: a song factory with an incredible house band and some of the greatest African-American voice talent of the generation.

The latest in the Legacy label’s long line of Philadelphia International reissues and compilations is an absolute jewel: a full concert from June 1973 presenting the label’s early greats (Billy Paul, the O’Jays, the Three Degrees and Harold Melvin and the Blue Notes) in a showcase setting, emceed by the late, great Don Cornelius.

The concert, recorded at a CBS Records convention at the Fairmont Hotel in San Francisco, marks the only time the label’s stars performed live with the massive MFSB orchestra (supposedly “Mother, Father, Sister, Brother,” though Cornelius garners a laugh when he asks, “Mother what?”).

“Golden Gate Groove” is an expertly performed and impeccably recorded set-every guitar wah, cowbell crack and timpani roll is clearly articulated. Unlike many long-vaulted sets from the era, this one actually sounds like it was intended for release.

One can visualize a Soul Train line breaking out during “The Love I Lost” or, perhaps more appropriately, during MFSB’s rendition of “TSOP,” the “Soul Train” theme song. Truly, this band could do it all. Their swinging take on Curtis Mayfield’s “Freddie’s Dead,” one of the album’s few non-Gamble/Huff compositions, is a highlight among highlights; the driving funk that backs Billy Paul on “East” is another.

And then, of course, there are the singers. “Song stylist” Paul shows off his signature dynamic range on an extended “Me and Mrs. Jones,” while the incomparable Theodore “Teddy Bear” Pendergrass shouts and pleads his way through a too-short Harold Melvin and the Bluenotes set, his spoken breakdown on “I Miss You” turning on a dime from emotional to hilarious.

Where the label’s other acts seemed like East Coast responses to the Motown sound, girl group the Three Degrees provide the most direct line to that history with the lively “I Didn’t Know,” though they were never themselves a Motown act.

The legendary O’Jays close with an engaging four-song set, bookended by the timeless “Back Stabbers” and “Love Train.” Philadelphia never sounded better.