Thanks for the responses.
PiedPiper: my speakers are Aerial 9's, my room is 14x25 and soundproofed with ASC wall-damping. This sort of traps bass in to some degree, but the issue is that the Aerials were designed with 'thick bass' in mind; they have 4 7' woofers for low frequencies, 1 6" for midrange. They overload my room. My room is also a home theater so the speakers are on the short wall, about 3' from front and side walls. Seating is at 12' from front wall and I can't change this.
The Aerials have downfiring ports. Instead of using the optional stands (which raise them a few inches, I'm using the stock plastic 1" feet). This seems to congest the bass slightly.
Dan: Your post intrigues me because I keep thinking that if I could could attenuate a choice woofer or two it might help. What is an L-pad? If you wouldn't mind describing what you're thinking of, I'd appreciate it.
I'll check out the leads for Rives and Marchand.
Thanks again,
Ian