Figured I'd update this post with some more info. I got my jamma harness completely wired and tested for continuity. Also got my coin door wired up, the control panel wired up with a kick harness, the game pcb, marquee, bezel, etc. Basically, i have a bunch of parts in place and am getting down to the point of only needing to build the cabinet itself.
Today, I got the monitor all wired up and turned it on for the first time. It was made from a WG 25k7xxx chassis and frame I bought from folks on KLOV, and a tube i took from a 25" Sanyo TV i got for free on Craigslist. Still riding that high from it successfully turning on and looking pretty good.
I'm now focusing heavily on the speakers. I know that Jamma is a mono only setup with very rarely a game that gives stereo output on Jamma. CPS2/CPS3 games all output unamplified, line-level signals through separate RCA connectors. So I've been wondering how i can get this cabinet setup so that it will play mono jamma games through both the left and right speakers, and also be able to easily play stereo CPS2/CPS3 games. I have two shielded, 8 ohm, 4 W speakers and yanked a 5 watt, 2-channel amplifier from a Logitech Z130 set of computer speakers. I needed to figure out how to get this all together so I could make an easy swap on the pull-out drawer, and also not damage any components.
I found out that a Line Output Conditioner (LOC) will take the amplified jamma mono signal and convert it down to a line level signal that I can then feed into the amp. The LOC arrived yesterday and is pretty simple. Four wires coming in (which I will connect to the L/R +/- jamma connector by using a two pin molex connector for each speaker line), and two RCA jacks coming out along with gain control for each channel.
The left speaker output from the Jamma Harness (which is the mono audio for games like SF2CE) will be connected to the amplifier via a Y-splitter RCA cable. This way the signal will be provided to both the left and right channels on my amplifier. If I'm playing a CPS2/CPS3 game, I will just unplug the splitter and plug the PCB's RCA connection directly to my amplifier, bypassing the LOC.
The audio amp will then have a 9-pin molex connector between the 9 wires I'll solder onto the amp board where the volume pot used to be, and the lengths of cord used so i can mount the volume knob in an easy accessible area in the coin door opening.
For power, this will come from a 12V DC connection and ground connection from the power supply. While the speakers came with an AC Adapter to convert AC to 10V DC, I don't see any issue in feeding it 12V DC since the amplifier chip itself (BT2025BH) is spec'd to run at 12 Volts.
Currently, the only thing I need to do is get some RCA cables and figure out how to wire them into the audio amp, then I also need to get some more molex connectors to make all the connections I will need to make. I'm hoping to get this done this weekend and test it all out by mounting the speakers to a scrap piece of board.
Below is a somewhat large sketch I drew up that details my plans.