First post, by pleonard
Those of us (un)lucky enough to have collected an Ultimedia PS/2 know that the audio features of this machine are a mix of good and bad: great front-panel amplified speaker with volume control and headphone/mic jacks, coupled to a terminally-unsupported audio card (M-ACPA or AudioVation, choose your MWAVE DSP poison). The question is: how to connect that great front-panel speaker up to a useful sound card?
As you might expect, audio is connected through a proprietary 16-pin connector that plugs into IBM's own audio cards. A few 3rd-party boards (ChipChat among them) include this "Ultimedia Header", but Creative's own SoundBlaster Pro MCV (CT-5330) does not.
Since the pinout has been documented by the PS/2 community...
...and since you can buy 2x8 dual row headers ...it should be relatively easy to solder up a R/L/Gnd cable from the line out jack on the back of the SoundBlaster Pro:
(believe it or not, those pins aren't shorted 😀 )
As you'd expect, best results are obtained by disabling the built-in amp on the SBPro. The result is very clean sound -- contemporary (1991) reviews of the Ultimedia mention how these machines' own sound hardware obviated the need for external speakers for most users. Best of all, you can completely uninstall the original DSP sound card. (Your sympathies for the original IBM sound card will dramatically decrease when you discover how many dozens of kb of RAM it requires to produce sound of any kind in DOS...!)