Getting relatively clean output from an old Sound Blaster card.

[endre1952]

I would like to record OPL2 FM music to make audio CD's and MP3's using real hardware. I've got an old Sound Blaster 2.0 ISA card (perhaps the only device that still remains of my favorite era of gaming, I bought it new in 1992) in my 386 SX40. It is noisy as hell. How could I get relatively clean output from it? My guess is: move it away from other cards, and perhaps use a CF card as hard drive. I would like to record OP2 music the following way: capture the FM data in DosBox, but play it back for recording on real hardware. By the way, which is the best card for recording OPL2 music? I just bought a CT-1330a off Ebay and will probably get it next week. This should be pretty cool, I assume it sounds exactly like those mono OPL2 Sound Blaster and Adlib cards, while capable of producing stereo FM music. I also have hopes of getting a CT-1600 real cheap (about 1 USD), only I can't seem to get in touch with the Hungarian seller at the moment.

I got a Sound Blaster 16 back in 1995. I was not especially impressed with it compared to the SCC-1 I owned at the time, and, as I recall, it didn't sound exactly like my previous Sound Blaster 2.0 and even earlier Adlib clone cards. I junked that SB16 eventually, since the line out had worn out and no longer produced a decent output.

Thanks for any advice!

[Laust]

In my experience, some computers are just more noisy than others. My 386 is also more noisy than the 486 I normally use. Using a CF card as the harddrive will definitely lower the background noise level. A trick I used to do, before replacing the HDD with CF, was to create a RAM disk and run the game out of that. After having spun down the harddrive via a DOS power management tool first, of course.  However, you might not have enough memory for that, I have 128MB in my 486

Since a lot of Yamaha's FM chips (including the OPL2/3) are digital in nature, it is also possible to capture the audio signal directly at the FM chip, removing all noise. Unfortunately, you need some custom hardware for that, like the old Adlib Digisnap project, so it's not really a practical approach.

[5u3]

You could take an AWE32 with OPL3 (not CMS), build a SP/DIF adapter cable and use a digital recording device.

[Locutus]

There are AWE32 with real OPL3 chips out there? May I ask which revision?

[Cloudschatze]

You could take an AWE32 with OPL3 (not CMS), build a SP/DIF adapter cable and use a digital recording device.

Seconded, per my own setup. 

AWEUTIL, by default, initializes the EMU8000 with equalization enabled (boosted treble, or so I've read), which is consequently applied to the OPL output. While it's not particularly noticeable or bothersome, if you're looking for a "flat" recording, you might want to disable the EQ.

There are AWE32 with real OPL3 chips out there? May I ask which revision?

Basically, anything with the CT1747 IC (CT2760, CT3900, CT3980).

[Locutus]

Basically, anything with the CT1747 IC (CT2760, CT3900, CT3980).

That's interesting. The CT3990 doesn't seem to have this chip anymore. Is the output really comparable to a real YMF262? Has anyone tested this?

[Great Hierophant]

That card should have a smaller chip marked CT-1978.  If it does, then the output will not be truly comparable to a YMF-262.  This has been tested on this forum.

[Cloudschatze]

Basically, anything with the CT1747 IC (CT2760, CT3900, CT3980).

That's interesting. The CT3990 doesn't seem to have this chip anymore.

The CT3990 was the first AWE32 to have that fantastic CQM chip instead... 

Is the output really comparable to a real YMF262? Has anyone tested this?

In both theory and practice, the output of the CT1747 OPL3 core is exactly the same as that of the OPL3-L or OPL4. Check the bottom of this thread though for more information:

http://queststudios.com/smf/index.php?topic=2416.0

I have some digital recordings at the top of that thread, if you want to do your own comparison.