Preout voltages and amps

[Konstantin 10+ year member]

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.

Click to read more...

 

[iceteebone 5,000+ posts]

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 10+ year member]

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 5,000+ posts]

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 10+ year member]

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 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 5,000+ posts]

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 10+ year member]

No, I left the same gain level.

**** pioneer.

 

[iceteebone 5,000+ posts]

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 10+ year member]

I have gain set to the lowest possible with both amps.

 

[WOT]

Sounds like headunit to me.

One works, the other doesnt....