If you have Active version then I will advice you to for Kenwood HU & 6" Kenwood door spk I had install kenwood for my former 75 BHP Active. Output of Kenwood HU & kenwood spk is so dynamic & perfect reproduction of frequency. I will PM you afterwords. By reading my thesis you will come to know how kenwood is 'Baap of the baaps' of all car audio. People install additional amp,s/w for getting desired frequency. Kenwood HU does not need this additional expenditure. Coz pre-amp (internal amp of HU) of Kenwood HU is capable to reproduce all frequecies correctly. IMO any HU need additional amp /subwoofer then that is weak point of that HU brand.