Maybe the horns and the voice coil could have different inertia values...
Yeah, that seems very reasonable. It also brings up another topic where whole inertia control is very limited: It only really works at very, very low values. I think last time this came up I ignored the issue since using the modwheel functions as a good alterntive to using the intertia control.
A better approach would be:
a. inertia defines a period of seconds to go between rates, eg, stop to min, min to max, control can be log for better control of smaller values.
b. separate controls be applied to horns and bin - this request - which is a very interesting proposal.
At the moment the closest I can offer to separated rates is that you disable rotation of the bass bin, then you are left with inertia of the horns.
Will have to review when I can make the change but it is accepted.