Ground noise after amp install

[littleape]

Was that the bilge pump being turned on and off with the engine running?

Engine not running, that was the blower being switched on/off/on/off.

 

[littleape]

It can also help if you drop the original "Ig switched 12V" that powers the head unit

Was thinking about doing that since its the last part thats still feed from the original boat wiring. I have a relay laying around maybe I'll give it a shot, a little skeptical but nothing else to do.

 

[littleape]

OK so I hooked up a relay for the switched 12V and noise was still there, I then ran the constant from the deck to the amps 12V input, which comes from battery, and boom noise is gone. Have not checked with engine running but the blower noise is gone.

So yeah, combination of a relay and constant directly to battery did the trick. There's still some minor hiss coming from either the deck or amp, not exactly high end stuff here, but its too low to hear in normal situation and does not go up with volume.

 

[sam am I]

Congrats!!! and yes, some hiss(self noise), esp. with the amp's gain is max'd is pretty common (SNR).

You can quantify this by disconnecting the radio's signal(RCA jacks) and shorting out the all the channels(+ to -) inputs of the amp and max'ing the amps gain settings......Any noise (hiss) heard is being self generated/inherent by the nature of amps circuitry/design.