I have a Marantz PM6004 and I'm using the high level outputs to connect to a Hsu sub. When I wired it up, the easiest way to use the high level outputs was to just put banana plugs on the speaker cables, plug the sub into the Speaker B terminals and then run the amp with speakers A and B both active (actual speakers on A, only sub on B). This seems to be working fine and I haven't noticed any problems (amp is cold to the touch after 8 hours of listening) but, I'm wondering if this sort of setup can damage or otherwise affect the amp. The Hsu manual says using the high level outputs doesn't put a drain on the amp but, I don't know if that still holds true in this configuration. I search and couldn't find a definite answer so, any advice would be appreciated.
(Wasn't sure if I should post this in the sub forum or receiver forum...)