Disco 2 TD5 ES - Head Unit Swap

Hi All,

First time posting since buying my disco backend of last year. Since buying the car I have spent a lot of time researching how to get Bluetooth audio function in the car as I realised it has the HK audio system. I finally decided the best way was to keep the existing CD changer and head unit and install a Parrot kit to get this working. The installation was quite easy however I was left with an annoying whine on the speakers which increased with RPM. I suspected that this was related to the lead I purchased from Just Car Kits to tone down the volume from the parrot device and prevent it being too loud after going through the HK system so I started to look at replacing the head unit altogether with the Pioneer MVH350BT unit which I had in my old Ford. Again this installed lovely, I used an adapted from a company called Nexxia to allow me to use the pre-amp RCA outputs on the Pioneer to connect to the car ISO block however I still had the whine (though it is less noticeable with the Pioneer). The next thing I tried was to get a pair of audio noise filters, these installed between the RCA outputs on the head unit and the RCA inputs on the ISO adapter cable I purchased however they have not completely stopped the noise. I have recently also purchased the necessary interface and patch lead kit to allow me to get the steering wheel controls working again with the Pioneer so I am looking to stick with this setup if possible however I wondered if anyone else has tried this and found a solution to the whine at all?

Please let me know if you need any further information about the car or the items I have used to fit the new head unit.

Rhys.

This is known as "alternator whine".
The usual method of stopping it, unlike reducing interference from sparking devices such as dynamos when you fit a suppressor across the offending terminals, alternator whine is dealt with by inserting a whine filter in the power feed line to the device suffering the interference.
Either of these should do the job:

Filter 1

Filter 2

Unfortunately neither of these is from the UK, so if the job is super urgent I'd advise talking to a vehicle audio specialist. The filter should be inserted in series with the supply to the Parrot system, by the sound of it.

Thanks Brian, exactly what I was looking for, I'll get one ordered and see what happens!

Rhys.

I also have had this issue and I have looked on alot of websites it seems to be to do with the earthing on the amplifier and the only solution that I can find on the land rover forums are to rewire the speakers and disconnect the amplifier I am in the middle of rewiring the speakers without removing the original wiring and connectors. I have been avoiding the cold weather at the moment so i hope to get it finished soon.

I am just installing a Sony head unit into my D2 Harman Kardon Alpine system and I am buying this little lot to do so;
https://incartec.co.uk/landrover/1343/1033/2049/165/Browser.aspx
These adaptors allow for the original fit amp, rear door subs and steering controls to be used.

Thanks for the responses guys, I fitted a filter as suggested but it didn't make a whole lot of difference. I am going to spend some more time looking at this with a friend who is more knowledgable with audio/electrical stuff next week, hoping a second pair of eyes will help me troubleshoot the issue. I hope you guys have better luck with your installs, I'll be sure to post the outcome of further testing after next week. Harry please let me know how yours goes as that kit you linked looks good, might have to look into that if I can't get this sorted with the kit I have already.

Rhys.

Not sure how a Parrot interconnects with the audio system but if you disconnect it and run the HU straight through into the amp do you still hear the whine?

Hello,

Just realized that I probably didn't explain the logic behind swapping the whole head unit very well... The new Pioneer unit has built in bluetooth so I don't need to have the Parrot kit at all. I have tried using the amplified output from the Pioneer and this worked without the whine however the output volume is too loud (volume 2-3 is about the maximum you can have it on) due to the audio effectively going through two amplifiers. I only get the whine when using the pre-amp RCA outputs on the Pioneer which I need to use to keep the volume correct. I have installed RCA filters between the pre-amp outputs and the RCA-ISO adapter however this didn't entirely stop the whine. I also had a friend look over the system and we basically verified that it all should be working okay, we also tried using a multimeter to check continuity on the earth wires to both the head unit and the amplifier so I'm not sure what to check next as the earthing seems to be okay. I might be tempted to get the amplifier interface that Harrymattson suggested as this would be using the amplified output on the head unit which I already know doesn't make the whine however this will have to wait until payday as I have already purchased a lot of kit to try to resolve this.

I'll post any progress I make with this for anyone who is interested though.

Rhys.

RhysP73 said:

Thanks for the responses guys, I fitted a filter as suggested but it didn't make a whole lot of difference. I am going to spend some more time looking at this with a friend who is more knowledgable with audio/electrical stuff next week, hoping a second pair of eyes will help me troubleshoot the issue. I hope you guys have better luck with your installs, I'll be sure to post the outcome of further testing after next week. Harry please let me know how yours goes as that kit you linked looks good, might have to look into that if I can't get this sorted with the kit I have already.

Rhys.

Click to expand...

I finished installing it all this afternoon and it all works a treat! Only thing is the Incartec web site is wrong for the Alpine head unit kit - you do not need to buy the RCA sub out to mini DIN converter as this is for the Becker system and not the Alpine.
The only buggeration is the the whole lot (2 converter boxes and the extra wires) takes up a whole heap of space behind the new head unit. So much so I had to remove the entire centre facia so that I could weave it all in and lose it so that the new head unit would fit. There is space under the support bar bracket to put it but it is damn near impossible without taking the facia off.
No additional wiring to do as the amp remote on worked from the Sony HU as standard through the adapters - not sure if other makes would though.
Sounds and looks good now - will be better when I repair the rear subs as all the foam rings have gone. Now on the work bench waiting for the re-foam kit to arrive.

Thanks for the update, glad to hear it went well. I received the amplifier interface yesterday and got it installed today successfully using the steering control interface I already had. I did end up butchering the lead I bought for the Parrot kit so that I could give the amp interface a separate power feed since it doesn't carry all the power signals needed for the steering wheel controls to work (the track skip buttons controlled volume but the volume buttons and the mode button were dead) with my interface kit. Basically I now have a Y splitter in the power feed, one branch feeds the amp interface and the other feeds the steering control interface which in turn passes power to the head unit. Output for speakers from head goes through the steering interface and then through the amp interface and into the cars harness.

Did you have to adjust the pots in the amp interface to lower the volume on yours Harry or did it just work? I did have a moment of panic when I tested mine and the box didn't appear to be doing anything but after a quarter turn anti clockwise on each of the four pots using a small flathead jewellers screwdriver it reduced the volume to a comfortable and controllable level so now 25 on my head unit is about the maximum versus about 5 before. It also is possible to make the kit fit under the support bar you mentioned without removing the dash but it took me a few hours to get everything tucked under there and connected up just adding one bit at a time starting with the amp box then adding the cables each side etc. So happy it all works, got all the trim pieces re-installed around the cage and underneath the head unit and it all looks good.

Thanks again everyone for the help and advice, really helped me to get this sorted

Rhys.

Hi Rhys - good stuff!
My Incartec interface was set at 50% from them and it seems to be OK without any further adjustments.
Re-foamed the rear subs and it all sounds pretty good now