OK, let's go! (I'm writing this on the SE/30, after checking what you said)

It would be interesting to see what the version register returns on the SE/30. On the IIci, using MicroBug with the command "DM 50F14800", the first byte it prints back is $00--version 0.

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So does mine...

1) The volume it loads into the volume register ($806) is a bit different: On version 0, it looks like the 3-bit volume is loaded into the upper 3 bits (5-7) of register $806. This also concides with what happens if I play around with the sound control panel and then dump the contents of it:
volume 0 --> $00

volume 1 --> $20

volume 2 --> $40

volume 3 --> $60

volume 4 --> $80

volume 5 --> $A0

volume 6 --> $C0

volume 7 --> $E0.

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These are exactly the values I read at $50F14806 if I change the volume setting via the usual control panel...

2) Another thing it does differently with different ASC versions is that it puts something different into register $802. For ASC version 0, it puts in $00. For ASC with a nonzero version, it puts in $01.

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Well, here we are a difeference: mine reads $02. FWIW, at $50F14801 is $01.

So...I guess it would be awesome to get a dump of what register $800 contains on the SE/30's ASC. Extra credit if you change the sound in the sound control panel and dump the register contents each time you change the sound like I did in my list above.

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Done ;-)

I haven't tried the custom ROM SIMM on the other compatible machines I have (IIx, IIsi, Quadra 700) although I don't think they would show any picture... but the sound should play OK, right? Should I try them too? Any other interesting test to do?

All the best,