VOGONS


First post, by RJDog

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So slowly building my DOS retro machine, and am now at a cross roads for sound card configuration. I have a Sound Blaster 32 (CT3600) which I would really like to use, and also have a CMI8330-based card (SB Pro compatible clone). Neither have perfect OPL-3 clones but the CMI8330 does not have the infamous hanging note bug that the CT3600 does.

I'm thinking of having both installed and enabled in the computer simultaneously and kind of get the best of both (imperfect) worlds. My initial thought is to have the line out of the CMI8830 patched to the line input of the CT3600. What are your folks' thoughts on this configuration, and recommendations for IRQ/address/dma settings these two cards to allow games to take advantage of these cards appropriately (i.e. CMI8330 for SB Pro, CT3600 for SB16/SB32/AWE32)?

Reply 1 of 9, by jesolo

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I would recommend the following settings.

CMI8330 = A220 I7 D1
SB32 = A240 I5 D0 H5 P330

In your Autoexec.bat file it will state: SET BLASTER=A220 I7 D1 T4

When playing back games that also supports MIDI, then you will unfortunately have to use the CMI8330 for digital voice playback (i.e., only Sound Blaster Pro support) and you can then use the SB32 for MIDI playback.
However, no DOS game uses 16-bit samples, so this is not a real problem.
On your SB32, you will just have to push up the Line In slider in your mixer utility so that it can route the sound playback from the CMI8330 through the card.

You didn't specify your hardware that you're using, but I presume your target games are from around 1992 to 1996, since prior to that General MIDI wasn't supported, with a couple of patches here and there for games developed prior to 1992 (only the MT-32 and its compatibles was then the MIDI device of choice).
If possible, disable your LPT1 (printer) port as well, to avoid any potential conflicts.

Reply 2 of 9, by dr_st

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RJDog wrote:

Neither have perfect OPL-3 clones but the CMI8330 does not have the infamous hanging note bug that the CT3600 does.

Do you plan to connect it to external MIDI so that you care about the hanging note bug?

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Reply 3 of 9, by jesolo

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dr_st wrote:
RJDog wrote:

Neither have perfect OPL-3 clones but the CMI8330 does not have the infamous hanging note bug that the CT3600 does.

Do you plan to connect it to external MIDI so that you care about the hanging note bug?

As I recall, even if you use the internal synthesizer of the card (i.e., the AWE chip) in conjunction with digital sounds being played back, it will still exhibit MIDI hanging notes on this model.

Reply 5 of 9, by jesolo

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I recall that my brother's Sound Blaster 32 (CT3930) also had the hanging MIDI notes (I distinctly remember this on Strike Commander, as the intro is playing, since he got that game with the sound card).

Reply 6 of 9, by RJDog

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Sorry, the machine is a Pentium 166; targeting a 1996(ish) build.

My thought as well was to use the CM8330 for digital/SFX and SB32 for music/MIDI. I do hope at some point in the future to get a Sound Canvas or MT32, or even direct it to the MIDI in on one of my contemporary machines for Sound Canvas emulation as suggested by PhilsComputerLab.

I'm not sure if the SB32 presents the hanging note on MPU401/MIDI out, but my understanding is that the SB32 will not encounter the bug if it is not simultaneously used for music/MIDI and digital/SFX out (i.e. use the CMI8330 for digital/SFX and SB32 for music only, as suggested).

Reply 7 of 9, by jesolo

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^ Correct on the last point.
There are some tricks that you can apply to enhance the MIDI quality on your SB32 by essentially loading better soundfonts. I have made posts about this previously (will look them up and update here).

Reply 8 of 9, by RJDog

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jesolo wrote:

CMI8330 = A220 I7 D1
SB32 = A240 I5 D0 H5 P330

In your Autoexec.bat file it will state: SET BLASTER=A220 I7 D1 T4

Thanks for the suggestion! If I remeber correctly I read or heard somewhere that older games (i.e. games that would target SB Pro) often have hard coded settings to use I7 as that was the default setting of Creative cards before Creative realized this was a bad idea due to conflict with LPT1 and started to default to I5. I don't particularly see myself needing use of the LPT port anyway, so I don't see that being a problem. Any games that I might want to try using the SB32 for digital/SFX would be new enough that I can probably set IRQ and Address settings within the game.

Thanks all!

P.S. I was able to connect the CMI8330 line out on internal header to the SB32 CD-in internal connector -- no external patching required. I doubt I'll use the CD-in fot actual analog CD audio anyway.

Reply 9 of 9, by James-F

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jesolo wrote:

I would recommend the following settings.
CMI8330 = A220 I7 D1
SB32 = A240 I5 D0 H5 P330

I run SBPro2 and SB16 together like this:

SET BLASTER=A240 I5 D0 H5 P330 T6
C:\SB16\DIAGNOSE.EXE /S
C:\SB16\MIXERSET.EXE /P /Q
SET BLASTER=A220 I7 D1 T4

This way the PnP SB16 is loaded first and the SBPro is jumpered to 220/7/1 so the BLASTER command is set correctly afterwards.
By default games will reach for address 220, but for newer games you can direct to 240/5/0 for SB16.

You can also combine the two to avoid the hanging note bug and the single-cycle DMA bug.
I loop the SBPro2 Line-Out (speakers) to SB16 Line-In, and from SB16 line out to speakers.
Mute the MIDI channel on the SB16 mixer or you will have a double OPL3 sound from both cards from port 388.

RJDog wrote:

Thanks for the suggestion! If I remeber correctly I read or heard somewhere that older games (i.e. games that would target SB Pro) often have hard coded settings to use I7 as that was the default setting of Creative cards before Creative realized this was a bad idea due to conflict with LPT1 and started to default to I5.

Here it is: http://www.oldskool.org/guides/oldonnew/sound
Yes, it is better to keep IRQ7 for older games that do not let you change the IRQ in their setup.


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