Electro Harmonix Bass Microsynth

This is a quite old design and it is noticable.
I'm a little disappointed in the octave region of the pedal. The octave down is decent but the ocatave up is rather weak. Square wave is excellent however.
There are also some problems with the tracking when playing notes to hard resulting in the signal is being cut. Properly muting string when not playing and between notes eliminates almost entierly.
If you are looking for a pedal that does octaves there are better alternatives. EHX's newer POG and HOG pedals comes to mind.
The filter section is what makes this pedal shine. It's not very interesting by itself but when combines with the square wave and some octave down some really nice synth sounds.
I yet to find a use for it in a song however.