PinSound Stereo 2.1 Harness for Bally/Williams
By using the integrated stereo and fader full tone equalizer, you can finely tune the original speakers to ge the best audio response.
In order to be able to use the stereo and the center independent settings, you need this to rewire the Bally/Williams machines to stereo. For this, you can follow this guide or buy this ready to use. You will need 10min and and iron solder. This modification can be easily reverted.
Note: this modification is not required for Data-East as speakers wiring is factory stereo 2.1.
Of course, you can always change your speakers for better one, but keep in mind that you still have to rewire in stereo/independent channels.