You might want to try using the RCA outs for your upper range signal and the LCR outs for your bass. There's a little difference in the gain, but I see no difference in the quality.
When you bi-amp, aren't you eliminating the speaker's internal crossover?
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HT:
990/770
Oppo BD83SE
Pioneer Elite DV-47A
Magnavox HDMR513h DVR/DVD-R
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Monster power centers-2
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JVC AL-A158 Turntable
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LFM-1EX
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Family room:
OPPO 970
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