Further to the matter of sound, a number of people complain about scratchy sound or sound that comes and goes. There's no surprise in saying that this is usually the potentiometers and capacitors on the two audio boards "Sounds Plus" and "Vocalizer". Since these two boards are nearly exclusive to the Xenon machine, I took the liberty of buying a pair of them, relatively non-working, from a fellow Pinsider. I tested them out in the Xenon machine and there was hardly any functioning game sound. The following steps were taken.
I purchased a complete set of replacement capacitors for both boards. They cost only a few dollars and only take a few minutes to replace, especially if you own a good desoldering tool. The go-to place to order these as "kits" is Great Plains Electronics. However, they seem to routinely be "out of stock" on the kits. Still, if you read the description of the kit parts, you can then order these replacement capacitors individually from Great Plains, or other sources. Here is the description of the capacitors from Great Plains web site:
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---> Part Number BALLY-S56E-KIT
Bally AS-2518-56 Electrolytic Capacitor Kit
Electrolytic capacitor set for Bally AS-2518-51 (Sound Module) and Bally AS-2518-56 Board (Sounds Plus Module)
Kit includes all new, matching capacitors:
C5 and C13 (2 Capacitors):
Original = Axial Electrolytic 1uF, 50 Volt
Kit = Axial Electrolytic 1uF, 50 Volt or 1uF, 100 Volt
GPE part number CEA-1uf-50V-RMD or CEA-1uf-100V
C7:
Original = Axial Electrolytic 470uF, 6 Volt
Kit = Axial Electrolytic 470uF, 16 Volt or 470uF, 25 Volt
GPE part number CEA-470uf-16V-RMD or CEA-470uF-25V-RMD
C8:
Original = Axial Electrolytic 1000uF, 16 Volt
Kit = Axial Electrolytic 1000uF, 25 Volt
GPE part number CEA-1000uF-25V-RMD
C15:
Original = Axial Electrolytic 4700uF, 25 Volt
Kit = Axial Electrolytic 4700uF, 25 Volt
GPE part number CEA-4700uF-25V-RMD
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---> Part Number BALLY-S57E-KIT
Bally AS-2518-57 Electrolytic Capacitor Kit
Electrolytic capacitor set for Bally AS-2518-57 Vocalizer Module
Kit includes all new, matching capacitors:
C11:
Original = Axial Electrolytic 1uF, 50 Volt
Kit = Axial Electrolytic 1uF, 50 Volt
GPE part number CEA-1uF-50V-RMD
C25:
Original = Axial Electrolytic 100uF, 25 Volt
Kit = Axial Electrolytic 220uF, 35 Volt
GPE part number CEA-220uF-35V-RMD
C25 = Power filter capacitor with higher capacitance value is recommended.
Notes:
Higher voltage rated capacitors are a good substitute for lower voltage rated devices.
Some boards were constructed with higher capacitance values than listed in manual. It is recommended to use higher capacitance value for better power filtering for this assembly.
Observe proper polarities when installing parts.
Improper installation can result in damage and/or injury.