Both of the sound cards were samples sent to HeadStart Computers circa 1988. HeadStart made low-end PC clones with bundled software, which was very unusual at the time. They jumped on the "Multimedia PC" bandwagon -- a Microsoft project -- and got all sorts of interesting gear, including then-exotic internal CD-ROM drives.
The "Killer Card" came with a couple of demo disks and xeroxed instructions. (The demos were very similar to the demos in the boxed Creative Organ card.) There had been computer sound cards before it, and in fact the "Killer Card" emulated the most popular, but it included a analog-digital circuit for recording voices and music, and a DAC for playing it back. This was a really dramatic innovation for a low-end PC; I remember upsetting co-workers while playing with it by playing a fire truck siren.
Well. HeadStart never released a machine with a sound card by the time it went under, but the "Killer Card" went on to become the Sound Blaster, which set the standard for PC audio. I saved the card, and lots of other odd stuff, from the "toss out" pile that accumulated as we cleaned out the office.
If it helps make connections: HeadStart was co-founded by Harry Fox, who was behind the SpectraVideo computers. These were really odd home machines that used a cp/m-like disk operating system created by Microsoft. I got a couple from Fox's warehouse manager; solid and functional compared to Atari and Commodore PCs, but the promised software line from Microsoft never materialized. I donated them to another basement computer museum in the mid-nineties.
