WPC speakers are all 4 ohm

Every speaker in a WPC game is 4 ohm; don't fit any other impedance. The speaker that fails most is the 3.5 inch backbox tweeter (the right one from the player's side), which has a crossover capacitor on its negative terminal. A 3.75 inch tweeter fits if its mounting holes are lengthened slightly.

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95

Related tips

• WPC sound board versions
• WPC-89 sound board layout
• The WPC sound board runs on its own
• Line out on DCS and WPC-95 sound boards
• WPC-95 audio/visual board part numbers
• Sound board beep codes, WPC-DCS and WPC-S
• WPC-95 audio/visual board LED and beep codes
• No audio output at all from the sound board

Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part Three, Clay Harrell (pinrepair.com)