For roughly the same price as being considered in this thread, you can’t go wrong with the Integral Audio Soundstage DSP Ultra, which includes not only amp, DSP, and replacement speakers, but also a separate custom box and subwoofer in the trunk. It integrates perfectly with the stock HKsystem and even retains parts of the HK system for rear fill action. Also, the tuning has already been done for the F80 as it comes with two different DSP profiles specifically for our cars and space for a blank third profile if you do want to tune it yourself. Product support is also outstanding and install was a breeze. I’ve had mine now for almost a year and could not be more pleased—true audiophile quality.
https://integralaudio.com/soundstagedsp-ultra.html
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