How do you make mixtapes?

Is there software to do this? You could record a DJ session with DJ software sure.

Can we make a fun tool like the dial in Teenage Engineering's new OB-4?

I love the momentum and physical sound of rewinding on the OP-1:


Rob Ochshorn also made a fantastic "seeking sound effect" here

...and a TMNT record scratch effect

Related: Video Hypnagogia/Phantasmagoria