Hi all, sent an e-mail to Steve about this, but thought I'd also ask the community to see if anyone else knows the answer
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I just reconfigured my two SE84UFO25 monoblocks to run in "differential balanced mode" using custom XLR->RCA adapters. My speakers sound really great!
There is a problem though: my subwoofers do not. I have two REL 212/SX subs that I connect via high level connection. When I was running the amps in "non-differential non-balanced" mono, the connection was simply red+yellow wire to the +'ve speaker out and black wire to the -'ve speaker out, on each amp.
Looking at the REL 212/SX manual, it says that when running differential mono blocks, it should be red+yellow to +'ve speaker out and to leave the black wire totally disconnected and floating.
When I do this, I get pretty bad 60 Hz hum from both subwoofers, and I don't really think they're usable like this.
My question is: has anyone else encountered this specific issue when running their SE84UFOs in differential mono, and is there a safe solution for where to connect the subwoofer's black wire to decrease/eliminate the hum? I don't really know how differential balanced amps work and am afraid to experiment and start connecting the black wire to things when there's a chance I could damage my amps.
Thanks for any advice, and Happy New Year!!