You should be able to find the information in the PinMAME source code. These are the Gottlieb sound source files:
https://sourceforge.net/p/pinmame/code/HEAD/tree/trunk/src/wpc/gts80s.h
https://sourceforge.net/p/pinmame/code/HEAD/tree/trunk/src/wpc/gts80s.c
These source files contain a few generations of Gottlieb sound boards so you will need to look the specific parts you need.