Build your own MIDI electronic drum kit or bass pedals (theoretically)

** this is all untested in real life**

Materials:
-12 contact mics with 1/4" cords ($30)
-MIDI drum brain with 10-12 trigger inputs (around $65 used on ebay, there is a new Alesis one for $150)
-MIDI to USB cable
-old organ bass pedals (free from trash)

-This may seem expensive but if you know how much the pro things cost its not. All you have to do is connect all of this.
-You can build your own contact mics from Piezo transducers (usually bought in the form on "peizo buzzer" at Radioshaq.

Applications:
1. Janky electronic drums.
-simply tape a contact mic to any surface that you want to be a "drum"
-it's better if the surfaces arent in direct contact because then you dont run into stick hits activating more than one drum.
-you can use boxes or funriture or whatever.
-then just assign a drum sound to each trigger (there may be preset sounds depending on the drum brain you buy) and jam.
-there wont be any velocity sensitivity but you will be able to play drums on anything

2. Sampler
-you could arrange things similarily to the "drum set" but use a computer or other sampler to assign sounds/actions to each "pad"
-you can spread these pads out on the floor or whatever to make "sound art" or several people could use them in a "band" to trigger samples.

3. Bass Pedals
-if you got some old bass pedals from an organ, you could attach a contact mic to an octave's worth of notes and assign (via sampler or sampler program) a sub not to each, and play them polyphonically as bass pedals or sampler pedals .
-as a cost example, this will cost around $150 and do about 50% of what the $500 roland bass pedals are used for.