I was going to hack a cheap set of pc speakers and use the board to power the origional speakers in the cab, but then I got the idea to use the origional sound board as well. Can I do that, will it work just feeding the two wires from the computer to it? Its a gauntlet sound board.
So you are chopping up a complete working Gauntlet for Mame? So sad.
That sound board is useless to you for what you want to do, think of it as a sound card, like in your computer.
I will admit this is one of the stranger impossible ideas I have heard.
Or if it is an audio AMP (AR II, AR III, ETC) and not a sound board then yes it could be rigged, BUT in Atari titles those are also power supplies, and it will eventually blow up with no boardset attached.