Hiss from speakers

I have an Alpine Power pack 4-channel amp installed along with a new pioneer 2400 hu. I'm getting a hissing sound from speakers- the hissing increases with engine revs. I tried the ground loop isolators that were supplied with the amp and the noise actually got worse. Its not noticable when music is playing but it still drives me crazy. The amp ground is tied into the hu ground. Do you think an alternate ground would help and where would be a good place to ground the amp? Also, I really don't want to pull the HU out again so if i disconnect the amp ground and tape up the ground wire that was running from amp to HU, will that screw up the HU ground? THX.


Stan

 

First thing I can think of is your power wire and your RCA's are too close to each other which can cause interference.

 

X2 that is the most common reason for alternator whine

 

Agreed^ but also, what do you mean "not noticeable when music is playing"? When is it noticeable then?

 

Sometimes cats will crawl into the door panels at night when its cold.

 

In between tracks or while the Hu is reading the thumb drive. It is somewhat noticeable during quieter sections of music also.
This amp plugs into the HU via a wiring harness which has power and speaker wires. The rca inputs are run seperately and only get close at back of HU.

 

Amp takes power from your wiring harness??? I thought that amp power should be taken direct from the battery, not enough power in the factory wiring harness for it. My amp has power directly form the battery running along the passenger side (under the kick panels), and my RCA's run from the head unit through the center console. No interference, as the only time they are close is when they plug into the amp. No hiss except a little when I pause the music (which is normal).

 

He has a power pack amp. Im not very familar with those, do you even have RCA cables or is everything connected with wiring harnesses?

 

it has Rcas or speaker level inputs. Mine is hooked up to Rca's.

 

Buy a noise reducer. It will go away

 

http://www.tacomaworld.com/forum/off-topic-discussion/253634-wtf-cat.html

Yep

 

When I get that it has been a slightly loose connection from offroad vibrations. Replug everything and it went away.

 

Think I'll try this. You guys don't think it is a ground issue?

 

I put in a Power Pack this past week with my Pioneer 3400 HU and I'm getting the same thing. I also used the same ground for the stereo and the amp, so i'm thinking it might be that and the power wire running too close to the ground or RCA input wires. I'll live with it for now since I don't feel like pulling my HU out but when I got back in to install a backup camera I'll try and fix it.

BTW how is your sound with the HU and the power pack? I'm a bit disappointed with the sound quality on the stock speakers. I haven't messed with the crossover and the gains on the amp but I was expecting a bit more rich sound of out of everything right out of the box. I recently put in a JVC HU in my MR2 and it sounded nice and rich, so I was expecting something similar from this setup.

 

I think it sounds good. I have Alpine components in front which were installed prior to amp so I don't know how it would have sounded with stock speakers. I left the crossovers on the amp alone and use HU crossovers.