The original supply is going to be noisy as well.
Its a piss poor design that Midway didnt care to fix simply because "arcades are loud and no one is going to hear these noises." It also has to do with how the cabinet is wired. The Kick lamps and the +12 that is supplied to the logic board come from the same source. In one of my earlier posts I said that the Lamps and Audio Amp were on the same +12, that was wrong. (maybe not, see below).
If you powered the kick buttons from the coin door lights supply voltage they would still flash. There is a switched to GND output that comes from the SSIO that illuminates the bulbs when its enabled. Unless of course you mean to simply have the kick buttons lit all the time but thats lame.
Grrr... These schematics are stupid. On the schematics J5 pin 14 goes to "contr lamps." That sounds like CONTROLLED LAMPS to me. That would be those two kick buttons lamps and if that is the case then the Amp and the controlled lamps ARE connected to the same +12 source.
Either way its actually wired the lamps share a +12 supply with the audio and thats why you are hearing the pop/thump. Furthermore, moving them to the coin door supply wont help any because they are also connected to either the logic board or the amps power supply.
Try this for shits and giggles.
With the game on and and coined up pull one of the coin door lamps out and lightly put it back into place (we want to make the bulb flash). Do you hear a pop? I'm guessing you will.
The only advantage the factory supply would have over this switching adapter might be the extra capacitors but I doubt thats a factor here. The AS adapter has the unregulated +12 supply duplicated so I'm guessing thats not an issue.
Last thing, try LEDs in those two kick buttons. Or you could move the KICK buttons to +5 (or -5) and change the bulbs to 555's. That would isolate the buttons from the audio circuits for sure.
Is the pop/thump the only problem you're having with the sound?
Its a piss poor design that Midway didnt care to fix simply because "arcades are loud and no one is going to hear these noises." It also has to do with how the cabinet is wired. The Kick lamps and the +12 that is supplied to the logic board come from the same source. In one of my earlier posts I said that the Lamps and Audio Amp were on the same +12, that was wrong. (maybe not, see below).
If you powered the kick buttons from the coin door lights supply voltage they would still flash. There is a switched to GND output that comes from the SSIO that illuminates the bulbs when its enabled. Unless of course you mean to simply have the kick buttons lit all the time but thats lame.
Grrr... These schematics are stupid. On the schematics J5 pin 14 goes to "contr lamps." That sounds like CONTROLLED LAMPS to me. That would be those two kick buttons lamps and if that is the case then the Amp and the controlled lamps ARE connected to the same +12 source.
Either way its actually wired the lamps share a +12 supply with the audio and thats why you are hearing the pop/thump. Furthermore, moving them to the coin door supply wont help any because they are also connected to either the logic board or the amps power supply.
Try this for shits and giggles.
With the game on and and coined up pull one of the coin door lamps out and lightly put it back into place (we want to make the bulb flash). Do you hear a pop? I'm guessing you will.
The only advantage the factory supply would have over this switching adapter might be the extra capacitors but I doubt thats a factor here. The AS adapter has the unregulated +12 supply duplicated so I'm guessing thats not an issue.
Last thing, try LEDs in those two kick buttons. Or you could move the KICK buttons to +5 (or -5) and change the bulbs to 555's. That would isolate the buttons from the audio circuits for sure.
Is the pop/thump the only problem you're having with the sound?
