I use a REL and have been thinking of perhaps adding another, not so much for bass as for balance. I am using the Neutrik connector (I think this is called high-level connection?) in which the SW draws nothing but the faintest signal from the amp.
I would think doubling up the connections (ie the second sub) should be fine. But have not tried it.
Regarding position, this is one reason I have not gone to two subs yet. I am on a suspended wooden floor (basement below) and have noticed, when this down-firing sub is away from the walls it excites the floor more - simple physics, as there is more flex to the floor the farther you get from the anchor point, ie the wall). Of course, this would indicate that a corner would do best in that regard, but that excited too many room nodes, and I ended up with it a few inches from the left wall, and about 3 ft from the left speakerm, more or less in a plane with the speaker baffles.
Am concerned that bringing the sub too close to the speaker would cause some 'bounce' in the speaker (mine are not too heavy - only 60 lbs) and smear the sound from the mains.
I would think doubling up the connections (ie the second sub) should be fine. But have not tried it.
Regarding position, this is one reason I have not gone to two subs yet. I am on a suspended wooden floor (basement below) and have noticed, when this down-firing sub is away from the walls it excites the floor more - simple physics, as there is more flex to the floor the farther you get from the anchor point, ie the wall). Of course, this would indicate that a corner would do best in that regard, but that excited too many room nodes, and I ended up with it a few inches from the left wall, and about 3 ft from the left speakerm, more or less in a plane with the speaker baffles.
Am concerned that bringing the sub too close to the speaker would cause some 'bounce' in the speaker (mine are not too heavy - only 60 lbs) and smear the sound from the mains.