Thread: Nexxia radio fitting kits for P38A

Yes, I saw that, Flo. It also mentions that if the amps are Nokia the problem may not be solved that way but one might need isolation transformers.

My car is a very early build so I suspect it may have Nokia amps.

Originally Posted by p38arover

Yes, I saw that, Flo. It also mentions that if the amps are Nokia the problem may not be solved that way but one might need isolation transformers.

My car is a very early build so I suspect it may have Nokia amps.

Received the nexxia kit, everything was wired since i choose the kit PC3-09-Kit with radio surrounds, antenna adapter

Sounds good except an amp noise that you hear at low level or during mute/aux/phone mode.

Sent a mail to nexxia for advice.

Hi Florent,

It seems like you bought the same kit as me and are having the same problems.

I'll pull the radio out today and try disconnecting each RCA plug in turn to see if that make any difference to the buzz. Then I'll pull the door cards off to cehck the amp earthing.

If it makes no difference, I may need the isolation transformers - another 30 pounds plus post.

Buy PC8-101 Car Stereo RCA Noise Filter

I'm starting to wonder if it's worth it.

Originally Posted by p38arover

Hi Florent,

It seems like you bought the same kit as me and are having the same problems.

I'll pull the radio out today and try disconnecting each RCA plug in turn to see if that make any difference to the buzz. Then I'll pull the door cards off to cehck the amp earthing.

If it makes no difference, I may need the isolation transformers - another 30 pounds plus post.

Buy PC8-101 Car Stereo RCA Noise Filter

I'm starting to wonder if it's worth it.

Hi Ron,

Yes, same kit so same solutions given by nexxia.

"
You will need to add new wires from the car door to the chassis amplifier.

More common problem is interference in which case you will need PC8-101 to stop the interference."

PC8-101 is a standard RCA filter.

I tried running the headunit without RCAs and i have the dzzzz noise from the door amps. Plugged old HU and it stops, i think it's more a ground problem of the headunit. I'll try to add some wires from the chassis of the new HU to a good known ground.

So i don't think RCA filter will make any difference but will buy one and try in front of the caraudio accessories shop.

Since i had a matchmute box to wire in the Parrot kit with the Clarion Diversity, i'll trash that thing first.

Anyway, beside that the sound of that new Clarion is perfect with much more power (no more saturation at high levels).

Downside is the blue illumination of the HU that makes the P38 looks like a ricer since it doesn't match the green factory lights.

I may try to change color the HU later... for a more neutral white

G'day Flo,

I pulled the new HU today and unplugged the adaptors. The buzz mostly disappeared but I noticed that I could get it to come and go by movement of the wires on the RCA leads. I stripped off the heatshrink tubing and found faulty wiring. I've fixed that but the overall buzz is still there. As you say, plugging the original Clarion back in gets rid of all the buzz.

The next job is to try an earth wire back from the amps to a common point with the HU.

I think the RCA noise filter is actually an isolation transformer. I tried buying some today but none in stock at my local auto or electronics shops. One auto parts store will have one in for me by Monday. I'll try it out. I could make one tomorrow as I think I have some small isolating transformers in my boxes of electronic parts.

My Fusion CA-IP500 HU also has blue illumination. I can change the lighting around the knobs from blue to white (done that) but the blue screen doesn't look too good. I could use more drive out of the HU RCA line level outputs.

I may have to pull the HEVAC out to be able to put all the cables and connectors down out of the way of the HU.

Originally Posted by p38arover

G'day Flo,

I pulled the new HU today and unplugged the adaptors. The buzz mostly disappeared but I noticed that I could get it to come and go by movement of the wires on the RCA leads. I stripped off the heatshrink tubing and found faulty wiring. I've fixed that but the overall buzz is still there. As you say, plugging the original Clarion back in gets rid of all the buzz.

The next job is to try an earth wire back from the amps to a common point with the HU.

I think the RCA noise filter is actually an isolation transformer. I tried buying some today but none in stock at my local auto or electronics shops. One auto parts store will have one in for me by Monday. I'll try it out. I could make one tomorrow as I think I have some small isolating transformers in my boxes of electronic parts.

My Fusion CA-IP500 HU also has blue illumination. I can change the lighting around the knobs from blue to white (done that) but the blue screen doesn't look too good. I could use more drive out of the HU RCA line level outputs.

I may have to pull the HEVAC out to be able to put all the cables and connectors down out of the way of the HU.

Lots of work and testing this afternoon for me.

1)Tried the RCA noise filter and...as expected it doesn't work. That kind of thing is used when you have buzzing noise with RCA but not without those.
Since we have buzzing noise even without RCA, those can filter what they want but we get no good result.

2)
Found many things during my tests :
-buzzfrom the medium and tweeter only. Bass speaker do not produce any buzzing.

-buzz can be stopped by grounding those 2 speakers (medium and tweet) BUT this stops the sound too.

-tried to ground the amps using black cable number 6 to bare steel : no change

-black wires from nexxia kit and not wired to anything can be wired to a negative speaker wire from 10 iso pink plug and provide a much clearer sound (voice) and attenuate the buzz slightly.

3)Bought a line output converter high level to low level (level attenuator).


Looks like i should wire this into front speakers wires on 10ISO plug then find a male-male RCA adapter to wire that converter to the HU.

i thought the nexxia kit did that job.

Then if that doesn't work, i trash everything and bypass door amps using crossovers like i read on landyzone.co.uk

Originally Posted by p38arover

G'day Flo,

I pulled the new HU today and unplugged the adaptors. The buzz mostly disappeared but I noticed that I could get it to come and go by movement of the wires on the RCA leads. I stripped off the heatshrink tubing and found faulty wiring. I've fixed that but the overall buzz is still there. As you say, plugging the original Clarion back in gets rid of all the buzz.

Ron,

Since your stripped off the heatshrik tubing, did you find any attenuator circuit like Ray Ambler advice

Aftermarket Head Unit Adaptation for Range Rover 4.0/4.6

I think this what we need mate

Flo

Originally Posted by 996TURBO

Ron,

Since your stripped off the heatshrik tubing, did you find any attenuator circuit like Ray Ambler advice

Aftermarket Head Unit Adaptation for Range Rover 4.0/4.6

I think this what we need mate

Flo

That all i am running and it seems pretty good to me - see earlier post for picture of the attenuator i built.