Hi everyone. I have searched the site high and low for an answer, but so far haven't been able to find out a specific answer. I see that many people have purchased the Audio Control LC6i and various other LOC's as a means of converting the speaker level outputs to amplifier inputs. I understand the need for converting the signal levels completely.

The part I am confused on is the frequency response of the stock system in a 2009+ F150, mine is a 2011. I know some stock stereo systems will attenuate certain frequencies to avoid damaging the speakers, most likely through some kind of internal crossover. I also understand that units like the LC6i will take the signals from multiple speakers, sum them together, and produce a 'flat' signal to send to the amps. So this still leaves me with a couple questions that I have not yet found answers for:

- Does the stock system in a 2011 F150 produce a flat signal, or are some of the lower frequencies attenuated creating a need for a unit like the LC6i?

- If not, wouldn't a less expensive LOC work just as good from a sound quality perspective?

- If the LC6i (or similar units) produce a 'flat' output signal, does this mean that changes to the head unit 'bass' and 'treble' settings will yield no change to the music?

I am about to begin my build as soon as I figure out what to do about the LOC. I'd like to not lose any part of the frequency spectrum, but I'd also like the ability to adjust the bass and treble at the head unit. I'd appreciate any help you can offer.

 

Also, one additional question.

- Are the signals to the front doors and the rear doors the same? If so, then summing them would change anything, would it?

 

i would like to know the answer to this as well but on a NAV system. I plan to upgrade all teh speakers and subs but was told that the even the stock NAV HU will clip the lower bass freqs. What would be the best option to retain the stock NAV HU and get full range sound from aftermarket speaker and subs?