Thanks, Brainiac!
Still remember the little monthly Jiffy of Valve mag in the letterbox. Happy times.
It's the original Whammos, not the S8 (I got the S8 kit over a decade ago, but the Japanese postal system posted half of it back, then everything went tits up for me here, and got left by the wayside.)
I considered the ST, since it has made its way into the S8 for some people.
By the way, I installed the Whammo's in a friend's HT setup, and watched Castaway - the Whammo's make watching the airplane crash sequence utterly compelling. The Whammo's go LOUD.