I have found a more serious difference:
awe32 works fine with Tie Fighter floppy
sb32pnp and awe64 don't 😀

edit:
for those cards you need old aweutil.exe (or you won't hear any music)
you also cannot run the game twice or run music test twice, or run game after testing music, cause music hangs up the second time 😉

sb32 is not awe32 compatible. sb32 do not have ASP (Advanced Signal Processor) which is available in awe32.

If you get awe32 and throw away ASP processor you will have sb32.

The ASP is sometimes called CSP (Creative Sound Processor).

The ASP (or CSP) was almost never used in games. I found it only in "PC RALLY" game.

ASP can add Qsound pseudo 3D effect. ASP can compress/decompress wave files in hardware. That is all it can do.

It was very expensive and rarely used. That is why Creative thrown it away and renamed card from awe32 to sb32 to sell it cheaper.

awe32 and sb32 have on-board 1MB of GM midi samples. The synthgm.sbk can be used without RAM because it only set patch names to instruments in ROM memory so aweutil or windows can exactly play GM midi music.

The synthgs.sbk and synthmt.sbk needs RAM to work because they add instruments in RAM to ROM bank. Both combined gives you GS or MT-32 compability. The games for MT-32 often uploads instruments to real MT-32, the awe32 in MT-32 compability mode probably can not do that. So emulation will not be real. I did not had MT-32 so can not tell for sure how looks MT-32 compability and quality.