The whole rhythm section was the Purple Gang.
4 seconds sound clip from the The Blues Brothers (1980) movie soundboard.
You can hear this line at 02:19:32 in the Blu-ray version of the movie.
Quote context
[...]
- Let's rock. Everybody, let's rock.
- Everybody on the whole cell block was dancing to the jailhouse rock.
- Spider Murphy played the tenor saxophone.
- Little Joe was blowing on the slide trombone.
- The drummer boy from Illinois went crash, boom, bang.
- The whole rhythm section was the Purple Gang.
- Let's rock. Everybody, let's rock. (2)
- Everybody on the whole cell block was dancing to the jailhouse rock. (2)
- Dancing to the jailhouse rock.
- Everybody on the whole cell block was dancing to the jailhouse rock. (3)
- Sad Sack was sitting on a block of stone, way over in the corner weeping all alone.
[...]