I have not seen any posts from Chad here recently, but last I heard he was in audio heaven running his Avantgarde of a high quality flea powered japanese SET amp. The Yamamoto shown still in his system listing I believe.
Avantgarde XLR subwoofer connection
I actually drive Avantgarde Uno with direct connection from preamp line out to XLR subwoofer connection, and i have the feeling that bass is greatly improved, compared to classical connection. Do you have the same experience? Marc from France ( forgive me for my poor english...)