I do want to do some investigation though and find out why they sounded so poorly bi-amped. I know a lot of people said it doesn't really help but it really shouldn't hurt either.
Correct: it shouldn’t hurt anything. Simplest solution is something wasn’t set up properly. In your descriptions, you kept mentioning that you had them connected to the Surrounds. Specifically, did you have the Rear/Back posts connected (which are the assignable ones)? Likewise, have you tried connecting any speakers to them at all, say as Zone2 stereo and testing to make certain something in the amp stage isnt wonky?
Hypothetically, your best bet for playing around with passive bi-amping would involve having two external stereo amplifiers, four monoblocks, or one 5-channel amp (like Emotiva or Outlaw, for example, where each amp channel is rated to put out a ‘true’ xxx w per channel, all channels driven)... If you were to do this, take a y-splitter from your L-Front pre-out, plug in to amp channel 1 and 2, remove the speaker jumpers, and connect amp channel 1 to the HF terminal, and amp channel 2 to the LF. Repeat for the R-Front and amp channels 3,4.
If you decide to seriously follow this endeavor, keep your amps matching, and for each speaker, make certain your speaker wires are the same length (left and right can each be different lengths, but left HF and left LF
MUST be the same).
Mind, I’ve kept that description on the simplified side, without even bringing in the value of bi-amping a matching center.
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Needless to say, you already know how most of us feel about passive bi-amping. It won’t hurt anything if you do it right, and if there is anything to be gained from it... it is generally considered to be very minimal and not really audible.
But using the AVR to do it, as I mentioned above, only takes juice away from all the other speaker terminals as you plug in more sources.
Hope that helps.
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