Most likely problem is the amp's ground wire or ground point. The ground wire should be big enough to handle the amps your pushing through it. 1000W amplifier could be drawing as much as 83 amps. I would use 4 AWG. Anything smaller than that could cause your noise.
The ground point should be close to the amp and a good ground source. Make sure you have metal to metal contact over the entire surface of your ground connector. Clean it up with a wire brush and coat with a dielectric grease to prevent corrosion.
Hope that helps
hi
i just installed a new amp into my car for my subs, but i kept my old amp for my speakers, when ever i turn the radio on a humming sound comes out speakers, i was wondering if there was any other reason then distributor noise. old amp is the 750 boss audio one
my setup
pioneer deck
2 jbl 1000watt 12" subs
bezerk 1000w mono bloc
boss audio 750 w am p
2 420 6'9
2 250 splits in front

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