PINsub Subwoofer Kit - Multi System for Other Williams Bally Systems System 6 or "C" we should have

or "C" we should have an integrated system that works for your machine

Knob is painted resin

It's all about the Speaker excursion

Background - It started with the JJPMAC:

PINsub Subwoofer Kit - Multi System for Other Williams Bally Systems System 6 or "C" we should haveThe PINsub Multi System adapter board kit (PINsub MS) allows you to cleanly connect your subwoofer or external amplifier system to ANY electronic pinball system using the included cabling. Now you can connect a subwoofer or external amplifier to your Williams Bally, System 10, 11, 11A, 11B, 11C, 3, 4, 6, 6A, 7, 8 & 9. PINsub MS Features: Easily connects to the cabinet speaker using POSI TAP adapters. Completely isolates the external subwoofer or