had my system installed at a pro shop here in Dallas, well not so pro after all, they have no idea what theyre doing...
my system: boston mids/tweets in front, jl audio stealthbox, alpine pdx amp driving both the bostons and sub. stock HU w/ nav. all other speakers disabled. all items are brand new.
i have a continuous and very audible hiss coming from my passenger side tweeter whenever the amp is on. HU does not have to be on. engine does not have to be on. hiss does not change with volume or engine revs. its a very high frequency hiss that sometime crackles when music is playing, esp music with lots of bass. the amp is on whenever the car is on. when i first start the car no hiss. as soon as i turn on the HU, hiss is audible, and if i then turn the HU off, hiss continues.
some diagnostics i did on my own: with hiss going i disconnected the RCA inputs, still hissing. i swapped the speaker sides, hiss follows sides and is isolated to one single channel out on the amp (channel 2).
what can i do? i dont have time to take it back to the shop as its my daily driver and the hiss is giving me a headache. i took it back once already and they jacked around with it around the fuse box for a while and said thats just the way it is. i will take it back hopefully in 2 weeks but is there something simple i can do on my own to fix the problem?
Does the amp have individual gains for each channel? If it does, try turning down channel 2.
They might have tuned it without noticing the balance was off on the HU and turned up channel 2 on the amp to even things out.
sorry forgot to add i already tried turning down the gain. its the alpine pdx-4.100 model.
it only has 2 separate gains, one is setup for the mids/tweets (channel 1 and 2) and one for the sub (channel 3 and 4). neither gain has any effect on the hiss. even turned down all the way the hiss remains the same. crossovers are appropriate (HP for the mids/tweets and LP for the sub). the hiss is definitely coming from only channel 2.
Also an ipod adapter is installed as well, but doubt that has anything to do with it. even when i hook up the ipod no difference.
Take it to Arlington. There is a shop on S. Cooper near mayfield that does award winnng systems. They are excellent to say the least. I have used them for years. I can't remember the name for the life of me. If your interested PM me on monday and i'll get it.
thanks for the help guys! took it in and the tech confirmed it was the amp and replaced it. i guess even alpine makes a bum amp now and then. sounds great now!
Corvette Store
HELP continuous loud hiss after "pro" install
