Hack That

Sonic the Hedgehog 2 (Virtual Console)

Slow Motion Sonic

On the title screen, press down twice to highlight options. Enter the options menu and then the sound test screen.
Using the directional pad to select sound files and the A button to play them.
Play sound files 19,65,09 and 17 in order.
You will hear a chime before playing track 17.
Exit by pressing Start and begin as normal but only this time you continuously press B to play one frame.