That's where the (mostly useless) CSP would go

The ASP/CSP chip is CT1748 but you'll probably have better luck finding an SB16 with it already installed. It's used by TFX for surround sound and that's about it.

http://dosdays.co.uk/topics/sb16.php

It arrived!!!

Got it all cleaned up,
Added the missing plugs,

It’s detected!!!

Sound is working!!

Now to find that missing chip…

Can’t seem to find it anywhere..

Noticed some jumper blocks that I missed.

All fixed.

There are also some ICs above where the missing chip is. Not sure what’s supposed to go there though. Or what they are for..

Might need some help from someone with the full card to make some measurements.

Hi, I believe that in order to be able to find a CT1748 chip, your only chance is to find a no longer working SoundBlaster 16 that mounts it and hope that it works. I searched (in vain) for that chip for years without finding it and I was looking not for a chip to solder but, the most common (so to speak), upgrade chip for card with socket.
The truth, as someone else said, is that you will more easily find a card that already mounts it (of course, given the current prices you will probably have to pay it well). Still good luck in your search 😉