You can use a transducer to excite any physical surface. This is how plate reverbs work for instance.

You could stick one (or two) transducers to a guitar or piano and then mic it up, and get the sound of the body of that instrument and parasympathetic resonance of any undamped strings.

The body is quite easily modelled with an impulse response, but parasympathetic resonance in DSP is still not great

re-recording digital stuff by playing the sound through something analog is a good way of making things feel more 'real', and can impart really interesting, hard to get character to a track. It's just time consuming to do, as the analogue world really only works in real time.

Speakers, themselves, have an absurdly broad range of nonlinearity, even within a single speaker, the way it behaves at 10% power and the way it behaves at 90% power can be drastically different. That makes them fairly difficult to model. Impulse responses are the soup de jour, and do a good job, but, they only really model a slice of what a speaker can do, ie, a given amplitude.

I agree! Or at least I’ve always been curious about this myself.