This was exactly my thought when I e-mail Jim about this very subject a few months ago. My impression from my e-mail exchange with Jim was that the issue with using the same upper enclosure is cost. It seems even with the smaller woofer the cost would still be close to the SS10.
I wasn't necessarily looking for a cheaper speaker, just one that I could drive adequately with the Quicksilver Silver 88 Mono amps.
Anyway, I'll just give Jim a call when I'm ready; might just be a one-off custom design.
