Thanks, everyone, for your opinions and advice, esp. to Doug, who I pestered/pelted with questions. The search still goes on, however. I will soon be trying out a pair of Vandy 2wq subs at home on a loan. They were remarkable r/t blending with the mains when heard in the store. I will also be trying out a pair of ported Focal 15" subs (driven by an older Levinson 200w/ch amp) in the next couple of days. I will post again in a couple of weeks after hearing the Vandy's and Focal's.