I passive biamp myself and use one amp in stereo for the LF and one for the HF. Even though there is no active crossover before the amp and the amp is sending all frequencies to the speaker the amp is only "loaded" at the frequencies the crossover limits. Although I didn't need the extra power of the second amp there was a sound improvement in my setup. I have biwirable speakers. As a former owner of an NAD 2200 I can't stress enough to remove the crappy stock hard wired power cable and replace it with something good. When I did it I went right to the fuse/transformer and bypassed the switch (when you open it you will see why) and used a power conditioners switched outlets as the power switch. HUGE improvement! I wouldn't try bridging, also aren't your speakers 4-6 ohms and not 8? You don't want to bridge that amp with a load under 8 ohms. I think you will like the sound best when one amp is loaded by the woofers and one by the top end. Let us know. And really change those cords!
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