Anyone used 240V-120V step down transformers?

At that size, I would advise using a stacked iron type. A toroid of that size will have substantial inrush current.

Toroids also have the dubious distinction of having too much bandwidth. A stacked iron type will filter out some of the crud on the AC line, which is always good.

This comes from someone whos uses toroids in all of his designs.............

(Just make sure that you put it far away from all of your gear.)

http://www.geocities.com/jonrisch/catch2.htm

Oh, just want to clarify -- the fuses blew in the one amp due to an extremely taxing dynamic passage of the movie I was watching -- my speakers are low impedence and large and can sop up just about as much current as any amp can provide -- after consultation with the amp designer, he said 10 amp fuses were OK, so I put those in.

The amp is plugged into one leg of the 240v, so is on a dedicated circuit and has a theoretical 20 amp limit from that circuit. The step down has another dedicated circuit as well (the other leg of the 240v), so it can provide 40 amps of current flow to two, three, or four amplifiers.

The fuse blowing had nothing to do with inrush, but there is a big gulp of that when the beast is switched on -- I just always keep mine on. I will email later when I have more time, but I just wanted to set the record straight on those points where I realized confusion might occur.

I mean, you just really got to hear what unlimited juice does for 100 lb. plus monster amps! I've had the second step down installed for five days now -- the last four days I've been giving my ears a rest -- that is a possible downside -- the sound is so clean, so dynamic, so powerful and intense, I think I really over did it! None of the usual clues that it is too loud are there, except your ears hurt afterward! -- that's when you know.

Maich
Which amps ,brands,models,do you have?A lot of amps are 100lbs and some are twice that weight and more
George

Maich, do you know what frequency your stepdowns are putting out? I want to step from 240V/50Hz to 120V/60hz - is it possible to change the frequency as well as the voltage?