TSOP (The Sound of Philadelphia)

"TSOP (The Sound of Philadelphia)"
Single by MFSB featuring The Three Degrees
from the album Love is the Message
B-side	"Something for Nothing"
Released	February 1974
Genre	Philly soul Disco
Length	3:43 (album cut) 3:29 (single version) 5:48 (12" version)
Label	Philadelphia International Records
Writer(s)	Kenneth Gamble and Leon Huff
Producer(s)	Kenneth Gamble and Leon Huff

"TSOP (The Sound of Philadelphia)" is a 1974 hit recording by MFSB (Mother, Father, Sister, Brother) featuring vocals by The Three Degrees. A classic example of the Philadelphia soul genre, it was written by Kenneth Gamble and Leon Huff as the theme for the American musical television program Soul Train, which specialized in African American musical performers. The single was released on the Philadelphia International label. It was the first television theme song to reach number one on the Billboard Hot 100, and it is arguably the first disco song to reach that position.

The song is essentially an instrumental piece, featuring a lush blend of strings and horns in the Philadelphia soul style. There are only two vocal parts to the song: a passage close to the beginning during which The Three Degrees sing "People all over the world!"; and the chorus over the fadeout, "Let's get it on/It's time to get down". The words "People all over the world!" are not heard in the original version. The version heard on Soul Train also had the series title sung over the first four notes of the melody, "Soul Train, Soul Train". This particular version was released on a 1975 Three Degrees album, International.

"TSOP" hit number one on the U.S. Billboard Hot 100 in the spring of 1974 and remained there for two weeks, the first television theme song to do so in the history of that chart. It also topped the American R&B chart (for one week) and adult contemporary chart (for two weeks). The Three Degrees would revisit the top of the AC chart later in 1974 with their hit single, When Will I See You Again.

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