various engines

Protosound 1 was not command control, it was a sound system and could be finicky, it apparently had problems if the battery lost charge before being replaced (I dimly recall), or would need to be reset. It has no interaction with TMCC.

Protosound is a full command control system along with sound. The DCS system that MTH uses is totally different than TMCC, and basically doesn't even know TMCC is present. It will operate in conventional mode (ie varying power to the tracks via  transformer), but won't have all the features DCS supports. In conventional mode you can control the PS2 engine via TMCC, you would need a powermaster hooked to the layout, with powermaster the TMCC control controls it and lets it set track power, thus controlling the speed of the engine (I think it also allows reverse control and whistle as well), it is the direct equivalent of running it from the transformer handle.

The other option would be to install the DCS system on your layout, that would unlock the entire PS2 functions. An added advantage of that is DCS can talk to the TMCC track module and allows controlling tmcc engines using command control.

yes i have a powermaster that is how i control my only MTH engine.i hear DCS is kind of hae

rd to come by with mike retiring.i wonder about the logistics and spare parts