OldSynths

So I played a Rhodes Chroma for the first time yesterday. It was really 
awesome. I noticed the "Thump" feature anytime you pressed a membrane 
switch or adjusted a parameter. What is that? A solenoid hitting the 
chassis? Are there any other synths that do that? That seemed to be a 
great feature. What's it called officially?

-Mike Walters
www.mysterycircuits.com