Great little unit this, plenty of different noises to be had out of it before even adding ultrahigh/slow pitch. Filled with techno and dancey-sounding samples rather than Jingle Bells, this can make some really quite usable noises!
My unit (which differs internally from similar toys I've seen on the net) has two black blob processors, one that plays the rhythms/loops and 'scratch pad' noises, and one that plays the 13-note keyboard and drum pad noises. Each has a resistor controlling pitch so adding independent fast/slow controls for each was a breeze.
Added a mono 1/4” line out, diode for a nice flashy envelope light, and removed the internal speaker so I had a large space to mount the controls. The device was ridiculously loud before I added a 500k trimmer pot anyway.
The unit has a 'aux/cd player in' socket and function on the front to turn on/off and control mix level. Can get some great feedback noises if you take a line off the speaker out and put it into the speaker in via some pots and capacitors, with the feedback being interrupted and modulated by the noise playing in the background, almost 303ish. Haven't done this though as turning on the aux-in messes up the rhythm pitch bends - must've chose bend points that are only high when the aux-in is enabled. Gutted.
Four pots in total, all 270k if I remember correctly, with an on/off toggle switch and a push button for each, allowing to lock the adjustment on or manually trigger the slowdown. Lots of fun to be had with playing samples, slowing them right down giving a tape-stop effect, and then slowly turning the speed back up and allowing them to groan out or suddenly come spurting back out at full speed.
When turned to a high pitch the CPU will crash, either giving silence or going off on a random aleatoric adventure. Seem to get best results with the rhythm/scratchpad as it seems to prefer looping!
http://www.doctea.co.uk/misc/mp3/Circuit%20bending/circuit%20bent%20mix%20me%20dj%202.mp3
http://www.doctea.co.uk/misc/mp3/Circuit%20bending/circuit%20bent%20mix%20me%20dj.mp3