Subaru BRZ OEM HU Amp Install Question
 

So I just purchased a 4 CH amp and some speakers for my 2015 BRZ. My question is can I just tap into the HU Front/Rears and sent them to the Amp? Will I require some sort of DSP or a "Cleansweep" device. I saw the LC6i audio control piece also. Does anyone know if the HU outputs a full range signal to the amp and if so should I set the Amps to Full Range or HPF? I would like to remove the amp completely and from what I can tell it only powers the door speakers? Any advice would be greatly appreciated.

Yes, it outputs full range and you will need a LOC of some sort, LC6i is a good choice. The factory amp powers only the door speakers, everything else (dash/rear) is powered by radio directly.

If your amp accepts high level input then you do not need a LOC device, but it can be useful to give control of line level feeding the amp.

Ok, the amp is a Focal FD 4.350 so it excepts the signal direct from the head unit. My concern was the HU did not send a complete signal to the amp. With that being said I would not need the LC6 or a cleansweep? What do I gain or benefit from it? Also do I set the amp to full range or HPF?

No you don't, but it can help if your signal going to the amp is too low or too high, it will give gain adjustment to give you control over this. Hpf setting depends on the type of speakers, are they a component system or full range?

The rears are coaxial full range and the fronts are 3-way component.

How do I know if the signal is too high or too low?? Do you mean volume?

If you set everything on hpf then you will have no bass, or possibly mids. Do you have a separate sub?

It allows you to adjust the signal going to the amp. I try to provide the amp a powerful clean signal so I can keep the amps gain lower.

Yes I will be getting a sub and a sub amp and splitting the rears input to both amps.

Also when set to full range does the crossover adjustment knob no longer function?

It should make the xover freq controls do nothing since you are telling the amp to output full range.

Alot of info in this thread:

http://www.ft86club.com/forums/showthread.php?t=42239

exactly what I was going to link :)
the rear amps signal will give you full signal for the fronts

Yes however the fronts from the HU also do? I would prefer to stay with the fader functionality. Not really NEED to but prefer to. I am tapping it at the HU. I was going to put a LC6 as well. I am also running new speaker wires and keeping al the factory harnesses and workin in tact. Removing the factory amp. I could tap in there also but prefer to remove the factory amp due to space limitations.

I would place the LC6i somewhere behind the headunit and buy the appropriate Metra plugs (70-1761 & 71-1761) to intercept the speaker wires from the factory plug (to avoid cutting any of the factory wiring). This would be an easy way to get all 4 channels. I'm not sure if it'll fit behind/under the radio but you can definitely find somewhere in the vicinity. You can then run RCA's to the trunk. You can use the remote amp turn on wire that is used for the factory amp to turn on your aftermarket amp and LC6i.

This way you can put all high level inputs into the LC6i in one place. If you mount in the trunk you can only get the door speaker wires from the plug that goes into the factory amp.