08-24-15: Sabai
Almarg,
The REL was connected to the speaker binding posts via the Synergistic Research REL cable.
My system is fully balanced from wall to speakers.
Unless you initially tried the Hegel prior to ever connecting it to the REL and found the symptoms to occur at that time, it seems quite conceivable to me that connecting the ground wire from the REL to one of the negative output terminals of the amp could have caused the symptoms you described, or possibly even damage. As I said in my previous post, it depends on the internal grounding configuration of both the amp and the sub.
Do you happen to recall, btw, if the channel in which the problem appeared was the same channel to which the ground wire from the REL was connected?
And if, as it appears, you are presently doing the same with your fully balanced S-30, and that works well, it's one more reason for kudos to Ralph/Atmasphere.
Regards,
-- Al