silversonic

i just install my new amp and keep hearing this hissing sound from all the speakers....front woofers, tweeters and rear speakers. This happens both with the engine on or off.

The quiet hiss noise is there even if i set the gain at min...i've tried puting a spare rca cords on the amp and unplug the rca input from head...the noise is still there...

i run the rca under driver side door sill...so is the noise pick up by the rca from the brake light? or is it the speaker wires pickup the noise?

Thanks in advance!

alex

bbsilver

Is it on all channels or just one? Does it happen with the ampped leads too? Try isolating where the noise comes from. You could have a flawed head unit. I've run into a similar problem before. One of my channels crackled no matter what the volume was.

matrix

This could be a ground loop. Make sure that both your head unit and your amp are grounded well. Best way to ground them both is to bolt them to the frame somewhere (you should remove the paint where your ground it....i know ouch ).

silversonic

yes the hissing is on all channels...how to isolate the amp leads?

maybe it's the amp ground...because i didn't hear the hiss when i swapped the headunit...hm...but i already scrap out the paint to the bare metal when i screw in the amp ground to the frame

is there a better ground for the headunit? I don't feel like scrapping the paint in the head unit compartment
currently i just use the ground wire from the stock stero pinout...

matrix

If you swapped the head unit and the hum went away, your amp is grounded fine. The problem is with the other unit. If you do not want to ground to the chassis in the stereo compartment (and scrap off more paint) you can do a couple of things:

1 - solder the new ground to the ground wire of the original head unit.
2 - If you can hide the wire, ground the head unit to a bolt on one of the seats. Try to keep it as short as possible.

MacGyver

SS,

What size amp are you using? If it's anything of any real power, I would suggest going with a separate ground.

The brake light won't cause any problems since it's a DC item (although there is a miniscule chace the wiring is carrying engine bay noise on it).

You said the hissing stopped when you swapped in a different head unit, so that should tell you something right there...

bbsilver

[QUOTE]Originally posted by silversonic
[B]yes the hissing is on all channels...how to isolate the amp leads?

maybe it's the amp ground...because i didn't hear the hiss when i swapped the headunit...hm...but i already scrap out the paint to the bare metal when i screw in the amp ground to the frame

is there a better ground for the headunit? I don't feel like scrapping the paint in the head unit compartment