Well, it's an oldie where I come from.
6 seconds sound clip from the Back to the Future movie soundboard.
You can hear this line at 01:27:03 in the Blu-ray version of the movie.
Quote context
[...]
- Come on, man. Let's do something that really cooks.
- All right. All right, this is an oldie, but...
- Well, it's an oldie where I come from.
- All right, guys, listen, this is a blues riff in B.
- Watch me for the changes, and try and keep up, okay?
- Way down in Louisiana Down in New Orleans, way back up in the woods among the evergreens.
- There stood a log cabin made of earth and wood where lived a country boy name of Johnny B. Goode.
[...]