I have DSP so yes it works with DSP.

It's as simple as tapping a line-out-converter onto the outputs going to the factory sub. The LOC then has RCA (low level) terminals that go to the BSW amp. The amp has speaker out which go to the BSW sub.

If you follow their install instructions it takes about 45 minutes. My way takes the better part of 3 hours, but looks factory. Either way works fine depending how OCD you are.

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2005 X5 4.4i Build 04/05 Maintenance/Build Log
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