I recently did my system:

front: Boston Pro60 components
Rear: Boston Pro60 axis setup
4080 w/ 10w6
jl 300/4 version 1
JL 500/1 version 2
3sixty.2 DSP

I have engine noise coming from the 300/4 amp and i don't know what is going on. each amp is individually grounded using 4 gauge wire. I grounded right inside the trunk on the small piece right behind the spare.
Is this a bad ground location or do i need the big 3?
deos my 300/4 support differential balanced inputs ?

 

What I would do first is see if your amps are grounded to bare metal. Then, are your rca wires running separate from the power wire? Have you tried bypassing the 3sixty.2 and just running the rca's straight to your 300.4 and see if the problem lies within the signal processor. Check and make sure the wires weren't crimped or broken anywhere.

 

Is your ground wire longer than 18inches?

 

+1 to both replies. Grounds need to be short and same or better gauge as power. Verify that your RCAs aren't near your power wires.

You should also upgrade the big 3.

 

i have a 2 gauge going in to a distro block then 4 gauge in the amp and 4 guage ground. the ground might be more then 18in ill check that and i definatly have the RCAs near... ill post pics of what that area looks like.

Thanks !!!