The SA1099 was a sound chip used in the Sam Coupe, some early soundblaster type cards and a few other things. It provides a complete sound system in a single DIP18 package needing nothing more than bit of discrete logic (and maybe an amp) on the audio side and some simple decode on the CPU side.

The board is little more than the reference 74HCT688 based address decode and the reference SA1099 implementation pasted together.

Errata: R3 and R4 are listed as 10K in the original board. They should be 1K.

Also note that like most of my 74HCT688 boards the address bits default to 1 unless a jumper is fitted. This makes it easier to slot them in with all the other cards that wire things to 0 based defaults.