Pavlo, I don't want to go off topic in a post about the OP's install, but I will say that like MOST amps (not all), the XD600/6 is not rated to handle a 2 ohm load on a pair of channels that are bridged. When we run the 600/6 in staggered 4-channel mode (4 channels bridged to two, two channels left in stereo), we use 4-ohm woofers.
If you'd like advice on your system, you might want to start your own thread.
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