No sound effects, no speech, distorted speech, no music, or low volume.

Pre-DCS sound board faults by symptom

Cause: No sound: the AD7524 DAC. No speech: the 55536 CVSD or the TL082 op-amps. Distorted speech: the 55536 or a 74LS74. No music: the YM2151 or YM3012. Low volume: the TL084 or TL082 op-amps.

Checks

• Note which part of the audio is missing to choose the chip to test.

Fix

• Replace the indicated chip.

Systems

• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics

Related tips

• Sound board beep codes at power-on (pre-DCS)
• Sound board RAM error at U9, wrong call-outs or no sound: replace the U9 RAM
• WPC sound board silent, no power-up bong: try the RAM first
• WPC sound board versions
• WPC-89 sound board layout
• The WPC sound board runs on its own
• Random stray sounds in attract mode after changing the CPU board
• Loud hum at power-up and the cabinet speaker burns: shorted audio amplifier chip

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