In order to get this example of feedback I ran my suitcase model Rhodes, which I confine to my studio, through an outboard processor with some nice amp modeling and cranked up the gain. For the processing I used an eleven year old Yamaha A3000 sampler. The A3000 allows you to edit and apply processing to an incoming signal and it has some pretty nice sounding effects. Once I had adjusted the processing I held down the sustain pedal on the Rhodes and let the amplification do the rest. Tapping or gently knocking the instrument also produced some nice sounds. Here’s a snippet of the results.

Rhodes Feedback