Rich,
It is some pro cinema amps built by a chap called Bob. From what specs I gather from Walter Dubuque, it is neither practical or safe to power this with 120 volts.
It needs a 240 volt supply delivering at least 15 amps I would say and a slow blow breaker to boot.
In my opinion, while you might be able to meet the running needs on a 120 volt circuit, you would never get it started. See the recount of my problems starting my amp case, that is less powerful than this, and you will see the problem. That is on the previous page of this thread.
It is built in the US, and is set at 240 volts because that is what it needs. You have to think welder, for the installation of this amp and not domestic HT.
You would never use a welder on a 120 volt supply, or at least not one that is any good.