Yep. On the same loop is no problem. Thanks. Just as with DCC, TMCC, Legacy, DCS, and other constant track voltage systems I'm familiar with. I didn't need to put it that way but chose to for some reason. Your first reply was not a waste of time. Now I know that when in a consist the sounds of the lead E-Z App engine are what you hear on your BlueTooth device or whatever you might have that also paired with such as a Bose Mini. Still wondering what you hear when two or more E-Z App engines are run separately at the same time.