I have a project Firepower with a slew of issues. I've been working on this particular issue for a few hours and I think it's time to call on the experts. The sound board that came with the game was sold as broken. I bought another board that was advertised as working. It was not tested. I transferred the speech card and ROM to the supposed working board. Speech works in game as well as in test. There is no in game sound. If I ground the pins of 10J3 the only sound I get is voice. Here is what I've done so far.

Replaced ROM socket
Reflowed all of the header pins
Confirmed all jumpers were the same as the original board
Checked voltages- 5v was a little low 4.89, -13.67, +12.22
Pin 37 of CPU shows activity with the logic probe

The ROM appears to be original with a factory label. (SOUND ROM 3). I put it in my burner and it verified. Here is the odd part, I tested it as a 2716, not a 2516. Not sure why it verified. This part of the tech I'm a bit blurry on.

Thanks!

I have the pot on the speech board at about half as well as the cabinet pot.

I kind of assumed no sfx meant an issue on the main sound board. I guess this was not a good assumption. I disconnected the speech board and my sfx were present. I will check out the usual suspects (sockets, cold solder joints) on the speech board and report back.

I replaced IC2 on the speech board. I found LM741 locally which I thought was a suitable replacement. I was excited to hear sound when I powered back up, but the speech is now super quiet. Even with the mixing pot all the way down, you can barely hear it. Is the LM741 not the right part, or is there more to my problem?

I decided to replace IC3 because it's the same chip and I bought extras. With a fresh LM741 installed it deleted speech all together. I reinstalled the old 1458 and went back to quiet speech. I'm guessing my part isn't compatible?

from what I can tell the 1458 is a dual op amp and the 741 isn't compatible because it's a single. Can anyone confirm this?

I had a Great Plains order I put together early in the week. Waited until the weekend when the checkout was supposed to be back open and it's still disabled. Something about long hours on his normal job. I hope he reopens soon!

I finally got the correct chips. Replaced both. With board plugged in, I get voice only. With voice board unplugged I get perfect sound. I'll probably replace all the sockets next. I hope it isn't the stupid ribbon cable.

I know I double checked the jumpers. At least I double checked W2-W13. W1 was hiding up top and I missed it. Stupid mistake. Cutting out W1 gives me sound and voice. I'm not sure if the sounds are all correct, but I'm a step closer.

I have a 2nd sound board as well. That one has w1 cut out but does nothing. I will use that troubleshooting guide to hopefully get that one up and running. Thanks for the resource.