Fulltone Distortion Pro?????

[AC30Dirty]

Do any of you guys know what gives the distortion in this unit its character? I like the fact that you can control the bass, mids, ttreble and so forth but was wondeing if I could put in some LED's to make it crunchier sounding. If the unit in fact uses diodes for the gain???

[Dragonfly]

IIRC, it is EXTREMELY close to the AMZ Overdrive Pro.