Here is some information that is not well published regarding Williams Type 1, Version 1 sound boards.
Per a WMS service bulletin, add two 10k resistors to open pads (See my pic) to "reduce susceptibility to noise".
To use a WMS "SOUND 1" labeled ROM or a 2716 EPROM containing the "SOUND 1" rom you need to do some modifications...
1. Change R14 and R23 to 4.7K resistors.
2. Solder pins 39 and 40 together on the 6820/6821 at IC3. If you do not do this, the PIA will not respond to the input connector being grounded yet the diag button will still produce sound. THIS APPLIES TO THE TYPE1 V2 AS WELL.
3. Change jumpers to as seen in my pic. THIS APPLIES TO TYPE 1 V2 AS WELL.
To use a 6821 PIA in place of a 6820, you need to do some jumpering on the V1 board (this is done by the factory on most sound boards except on very early ones). See my pic, it easier.... Blue Jumper wires on the solder side.
The V1 sound board is 100% compatible with V2 games like TimeWarp, Laserball, and probably even the arcade games that used the V2 board. These mods allow the board to be rebuilt more easily. Without knowing some of these tricks you can be left very confused why the board doesnt work right or only with certain components.
Hope this helps