Classic electronics fanatic David Larsson has designed a Inventive Sound Blaster reproduction with a distinction: it is suitable with IBM’s short-lived Micro Channel Structure (MCA), as present in chosen IBM private laptop fashions.
“Authentic Sound Blaster playing cards for the Micro Channel bus are fairly arduous to come back by lately,” Larsson explains of the reasoning behind his design, which is a second-generation enchancment on earlier work for each the MCA bus and the extra widespread ISA bus. “Plainly most sound playing cards for the MCA bus has line stage output solely. Fairly a couple of individuals have requested earlier than for it to be louder, so right here it’s. I additionally added a quantity management pot within the again.”
This reproduction Sound Blaster card is good for anybody who has a classic Micro Channel Structure system devoid of high quality audio. (📷: David Larsson)
Launched by IBM in 1987 for the PS/2 household, the Micro Channel Structure was designed to interchange the Trade Normal Structure (ISA) — primarily, although not solely, due to the menace “IBM suitable” clones posed to the corporate’s nascent private computing enterprise. Whereas MCA addressed most of the shortcomings of the ISA bus, it was additionally totally proprietary — and deserted by all when the extra open Peripheral Part Interconnect (PCI) commonplace got here alongside in 1993.
Owing to its quick lifespan, MCA {hardware} is skinny on the bottom — which is the place Larsson’s Sound Blaster clone is available in, standing in for the unique with some helpful quality-of-life enhancements. Maybe the largest: the power to route audio to the PC’s inner speaker. “[That] is one thing cool that the Micro Channel bus permits however the ISA bus doesn’t: the power to route the output of the sound card to the interior PC speaker (and even between playing cards, in order for you one card to report the output of one other, for instance),” Larsson explains. “The inner audio is amplified and thus managed by the quantity pot within the again.”
The board is supported in any software program with Sound Blaster or Adlib compatibility. (📷: David Larsson)
Different options of the cardboard embody full Sound Blaster compatibility, Adlib OPL2 help, a gameport for joysticks with MIDI help, and a 3 CD-ROM audio connectors. A plastic bracket ensures strong mounting in an MCA-compatible case, whereas Larsson has written that metallic brackets are deliberate as a $25 improve within the close to future.
The MCA soundcard is accessible to order on Larsson’s Tindie retailer now, priced at $125. Extra info on the design, and the maker’s different classic card recreations, is accessible on Larsson’s web site.