I have recently added an Amtrak with 9 lighted cars. The power drag is sufficient enough to cause the power pack to overload after 3 to 4 turns around the 10’ by 6’ layout. I am not considering DCC at this time. What I need to know is there a DC power pack available that pushes enough amps to solve my overload problems. I have been looking at the MRC Power Command 9500 and the MRC Trainpower 6200 to replace existing power pack. I have also been searching for a DC power Pack booster but I have been unable to find anything for DC systems that would boost the amps and allow for the power drag created.
You mention HO scale, but if you want a gutsy power supply, then any of the large-scale ones will definitely be more than ample–if not overkill. If I had to choose one for HO, I’d look at MRC’s “Controlmaster 20” power supply. It’s got 100 watts of power, which will give you 20 volts at 5 amps. That’ll be more than plenty for HO. I’d be a bit leary of some of the large-scale power supplies because some of them output in excess of 24 volts, which may be detrimental to HO equipment.