Hissing and aerial problem

[eyedee]

Having installed a complete new setup including front components, rear 5 x 7's, two 8" enclosed and ported subs powered by a JBL GTO 6 channel 600watt (6 x 100w) amp, there is a really annoying hissing coming through the speakers when the head unit is powered on. The noise is present when the engine is running or when it is off and there is no other engine interferance to complicate things. All the cables run are high quality and thick Roxford Forsgate with close fitted terminals for perfect fit. The power and remote cable is run down the left side of the vehicle, and the aux cables down the right hand side. I have adjusted the cross over network to best hide the hissing (which involved turning the dial to full db rating of +4db) and adjusted the amplifiers input and frequency dials plus the head units adjustable functions. But the hissing is still there! Any Ideas what it could be? Do some head units just hiss?

Secondly, as soon as I turn the power on the head unit on, the aerial lifts. Even when Ive got it playing a CD or my iPod through the AUX input, the aerial stays up! Ive checked that traffic alerts are not activated, which can keep the aerial extended. I can only assume a wire is incorrectly connected somewhere at the rear of the head unit. Any ideas? :confused:

[deanflowers]

what kind of quality are your phono leads as you can buy screened leads in order to cut interference from other lines

[eyedee]

Hi mate. From memory, they are double insulated aux cables, and the actual wire is 3mm thick (dont know what guage they are Im afraid). I dont know if they are screened as I never saw the packaging. I bought them from an ICE shop about 2 years ago and theyt fitted them directly to my car, they were about £20 each and they are 5m long. There was no hissing when I used them in my last car - or when they are connected to my old haed unit for that matter, so I would doubt it was those causing the problem?

[tinker-27]

hi i had the same problem even though i used good stuff,it can be a rca earth problem .you can get a type of filter that goes in the rca lead and it works !! they are cheap and stops the annoying noise ,does it get louder as you put more elecs on? mine did hope this helps (a suppressor in the power line did not work!) cheers craig

[babz_audio]

just done a full install in mates bmw with loads of wires running up and down the car, if you eart the actual rca cables they reduce the hissing sound by alot, small tiny earth would do

[eyedee]

Hi guys, I have obtained an inverter box (filter) to place on the RCA run from the head unit (I'll need three if it works) which I'll try just as soon as I get the time. The hissing doesnt get louder as the volume goes up though. And I'd been told those supressors are rubbish too.

Where abouts on the RCA's do you recommend grouding them?

Cheers :cool