What speed is your memory?

Are you using matched simms ? In my CT3930 manual it states 70nS or faster and the picture shows 3 chip parity simms though 9 chip will work, also most non-parity 8 chip should work though the 2 chip non-parity are known to cause issues.
2 x 1Mb, 2 x 4Mb, 2x 16Mb possible RAM combinations, mixing ram sizes or types will not function proper. I tested 2 x 256K and it also worked....

Please see attached photo. These are the two pairs I used. Both created garbled results.

I have a ct3600 although it’s not currently in a pc. I know you can run 32mb although I think only around 28mb is addressable in that case. I cannot tell the size of the first simms but I’d be interested to know if the choppy sound is still present if the total <= 16mb. Possibly you’ve already tried that.

As horun states, it should be 70ns or faster, but have you tried exactly 70ns simms? Apologies if the first pair in the picture is, but I see 60ns on the second pair.

I am not certain what the speed rating is for the first pair. I should look that up. But they are 2x1MB.

I ain't expert on these, but it looks like you might have managed to bracket it with too slow and too new.

This is interesting:

https://dosdays.co.uk/topics/sb_awe32_64.php#SB32

I've always been under the impression the SB32 can handle 32MB. That link says it can only handle 8MB. I know my SB32 detects and tests out 32MB, but that doesn't necessarily mean it can us 32MB. I will do some more testing with other sticks and see what I come up with.

I've used 60ns and 3 chip SIMMs before just fine on my AWE32

It can handle 2x16 MB 30 pin SIMMs, but you just can access 28 out of the 32 MB. You can go from 512K over 2M and 8M to 28/32M.
However, the SIMM holders are not designed for swapping modules too often. Be careful.

The top pair built on TMS4C1024 chips has 100 ns access time. The bottom pair is 60ns

Just to add to vstrakh's post.

The top pair are 1 MB simms each. Since there are 9 chips on each module, the one is for parity but, the access time for these chips are too slow in terms of the requirements for the Sound Blaster 32.
The bottom simms should work but, there might just be an incompatibility with the sound card.

I can confirm, the 32MB (2x16MB) pictured above does not work. Horrible chop. Sounds like the 1x2MB doesn't work because of insufficient speed. The below setup DOES work, but it sounds like absolute hot garbage. Bad distortion and cracking/garble. Though it isn't choppy so that is something.

I would describe it as distorted, garbled and phasing in and out with high to low modulation. Apposed to when I tried the 32MB setup where there was just blurbs of sound coming in with periods of silence at random intervals.

pico1180 wrote on 2023-04-07, 03:08:

I would describe it as distorted, garbled and phasing in and out with high to low modulation. Apposed to when I tried the 32MB setup where there was just blurbs of sound coming in with periods of silence at random intervals.

With all the issues you are getting, please make sure that all address pins on the new RAM sockets are properly soldered. A missing address bit may cause issues as you describe. The effect of a missing address bit can vary with RAM size. I used to think that the AWE32 synthesizer test in DIAGNOSE doesn't use the sample RAM at all, but that may be wrong, it could try to upload stuff from SYNTHGS.SBK and use GS banks if available. A simple RAM test that just fills RAM with a fixed pattern and then reads back that pattern won't detect addressing errors. This could explain why the RAM test passes and the synthesis still fails.

To verify the theory of addressing errors in the RAM: Please try any real-mode DOS MPU401 application (e.g. DOSMID) with AWEUTIL. As long as there isn't anything horribly wrong, having RAM installed should make no difference when you loaded SYNTHGM.SBK (refers to ROM only), but you are expected to get issues if you use RAM-based samples, e.g. from 2MBGMGS.SBK.

I tried 2x1MB SIMM (Goldstar with parity) on the card and no problem on the AWE test, that's all I can help, unfortunately.