I've been surfing a lot looking for pinball parts and all - not sure how I came across this, but the 1981 arcade ambience was really good.  

http://arcade.hofle.com/

On an ambience note, any ideas on improving the echo-sound in the room.   Its a basement game room - drywall walls and ceiling - but it gets rather loud and the non-pinball players start complaining.   Is its something as simple as bring in a few plants - or should I insulate a few of the walls I still have access too?

You could try "bass traps" these are insulation filled sonotubes (or square corners) with holes or a slit cut in the back.  You put them in corners and they tend to absorb standing waves that accumulate in the corners of rooms (that also tend to be the most annoying "thump, thump, thump" and echoing noises.  Not as good as a suspended ceiling or resilient channel and thicker than normal sheetrock or varied materials (like sheet rock over plywood), and staggered studs. Adding an additional layer of sheetrock suspeneded from the layer beneath it with resilient channel and/or acoustic caulk and make sure EVERY crack is caulked and vents are baffled goes a long way to reducing sounds. Walls that "move with the sound (and those that have insulation behind them) absorb the sound as heat and don't reflect it as much.  Other cures for sound echo include thicker carpeting and other underlays , a big heavy couch, a fish tank (questionable, but the bubbles will also help mask some of the sound).



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