what power supply to use

A new style ZW with 4 180 watt bricks puts out way more power than an old style. An old style is 250 or 275 watts input power and the new style is 720 watts input power with 4 180 watt bricks. You actually get considerably more power per output channel in the new.

Ron

You have more than enough power for what you describe.  One of your modern ZW's with four bricks have more capacity than both of the PW-ZW transformers.

Output power of 275W PW-ZW transformers is in the 220-230 watt range, the rest is lost in heat in the transformer.

Thanks. I like the safety and breakers of the modern transformers. I may use the old ZW to power lights etc.

thanks,

Howard

I'd put fuses or circuit breakers on the outputs of the old ZW, even for lights and accessories.