Seems they like around 17 volts AC better for me. I don't mind them dim. Just not so much that they look different than other structures they're next to. I have the MTH tank car unloading platform tied together with the tank. I think I need to have each on it's own power. The MTH is very bright at 17 volts. I could lower that one to get them at a more even brightness.
When I convert to LEDs, I add an adjustable dimmer control to them. So in this case, I could fine tune each structure's lighting.
