I know that's probably not the correct name for it, but I briefly saw one of these on the television the other day connected up to an upright in a piano factory. It appeared to have a "piston" for each key on the piano and would cycle through a set of notes in each octave or so, thereby playing every note on the piano within a short space of time - the noise was quite horrendous.

What is the purpose of this machine? Is it to test the resilience of the action, or to wear in the hammers, etc.?

Thanks in advance,

Dave

Jazzyd, the infamous piano pounder,used in some factories to pound in the action to compress felts and break in its new parts. This procedure will also reveal any broken or faulty parts needing to be replaced. The action will then be regulated again until it funtions at its optimum.Yes these machines make quite a racket.