PS is proto-disco, no doubt about it, and by 1973 had evolved into full-fledged disco when the Gamble and Huff produced MFSB’s TSOP: The Sound of Philadelphia, featuring the Three Degrees (another Philly Soul mainstay), became the first disco song to hit #1, as well as the anthem to Don Cornelius’ Soul Train.
In short, no matter the later cultural appropriation, disco is a Philadelphia sound, not a New York one.
