have been building different versions of these with mixed results.

the concept is unit that you can tap with your foot and produce a bass drum sound. it is plugged into an amplifier or pa system.

i first tried a piezo element which produced more of a knocking sound than a thump.

i next tried a guitar pickup mounted under a metal licence plate ( a ferrous one) and got better results.

i came across this product but it seems to me to be rather pricey for what appears to be a 2 inch speaker, an audio transformer and a 1/4" jack.

http://www.peterman.com.au/music/diy/stomp-box-bass-transducer-pickup-student

can any one help with information regarding the transformer specs required for this application as well as a north american/canadian source.

i would be plugging it in to a guitar/bass amplifier. guitar pickups range from 6k to 13k in resistance.


thanks
ets

 

Looks like a speaker as an inductive microphone, which makes a very small voltage AC signal when you "stomp" it.

Then an audio coupling transformer used to step up the low signal to a higher voltage signal ie 0.5v to 1v p/p needed for an instrument amplifier.

I'm only guessing but it's most likely the transformer is a low to high impedance type, and might even be a tiny speaker transformer, something like 8 ohms to 1000 ohms.

Also you will probably find the speaker cone has a flat weight glued to it so vertical forces on the speaker make the cone move via the inertial tendency of the cone weight to remain still.

 

thank you very much for your advice.
the weight on the speaker cone makes sense.

i'll start to search for a transformer source using those parameters.

cheers.