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Konstantin
01-29-2007, 03:55 PM
Hi, I havent been able to get a good answer by searching so I thought I'd ask.

I have a pioneer premier deh-p960mp hu with 6.5v preouts, and I have 2 subs. One for speakers and one for the subs. The first amp says max input 4V and the second one says max input 5v.

I am having trouble with some noises in random songs, so I thought it was maybe because the hu V's are higher then what the amps say they can take. I currently have my gains set to the lowest.

Amps are RF P4004 and MTX MXA4001. The noise problem I have is that during some tracks there is a little noise generated that sounds like a tinker bell. It doesnt happen with all the songs, so I am not sure whats going on. Plus, I had engine noise and it went away after I properly grounded the hu. I dont think its the wiring because half the songs sound right.

Thanks for the help.

iceteebone
01-29-2007, 03:57 PM
not your problem. when you are playing music, your are not putting out 6.5 volts rms. it's more like 1 volt rms. try regrounding everything and check your grounds using a dmm. ground your rca's too, but too high preout voltage is not your problem

Konstantin
01-29-2007, 04:04 PM
Thats what I thought.

But my concern is that most songs play ok, but some are dont. I've even sent the HU to pioneer to change the RCAs and the preouts. I regrounded all the car, and I did a ground fix for RCAs found on this forum. There are songs that sound right, at any volume level and with or without bass. But then there are others that get a noise problem, both with and without bass.

I have a pioneer deh-p7750mp and when I install it there are 0 problems. I'd keep that radio but its only 2.2v rated. Could the hu just be defective?

iceteebone
01-29-2007, 05:00 PM
try reseting your gains using the tutorial. what kinda noise are you hearing on certain songs? distortion? also 2.2 volts won't make a difference. like i mentioned earlier, when you are playing music you won't be getting 6.5 volts anyways

Konstantin
01-29-2007, 05:07 PM
try reseting your gains using the tutorial. what kinda noise are you hearing on certain songs? distortion? also 2.2 volts won't make a difference. like i mentioned earlier, when you are playing music you won't be getting 6.5 volts anyways

I'd say its like a cd jumping inside the cd reader :P Its like a bell, it starts at around sound level 10 (10/40), and if I turn it up the tinker sound gets louded. Below 10 it seems to go away.

iceteebone
01-29-2007, 05:17 PM
sounds like the radio. if your 7750 is working fine on lower voltage, then it's probably the headunit. did you reset the gain when you put in the 7750?

Konstantin
01-29-2007, 05:19 PM
No, I left the same gain level.

**** pioneer.

iceteebone
01-29-2007, 05:22 PM
No, I left the same gain level.

**** pioneer.

reset the gain with the new headunit. with the 6.5 volts deck, you should have the gain set pretty low and with a 2.2 volt deck you may not have heard the noise but it still maybe their. i suggest properly setting the gain for each headunit

Konstantin
01-29-2007, 05:40 PM
I have gain set to the lowest possible with both amps.

WOT
02-07-2009, 12:46 AM
Sounds like headunit to me.

One works, the other doesnt....