Alternator whine with aftermarket headunit

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jordanbutters
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Alternator whine with aftermarket headunit

Post by jordanbutters » Mon Jan 07, 2019 6:36 pm

I've recently installed a Kenwood DAB CarPlay HU in my RS4. I used a Connects2 loom and it's all playing nicely with the BOSE system, except I get audible alternator whine no matter what the audio source is. I've checked all the connections and nothing is touching where it shouldn't be.

Does anyone have any experience with curing this without resorting to ground loop isolators? Don't mind running a new earth or two if it means not losing sound quality (I understand isolators kill a lot of the bass quality).

jordanbutters
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Re: Alternator whine with aftermarket headunit

Post by jordanbutters » Sat Jan 12, 2019 9:27 am

No one else experienced this?

simroy24
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Re: Alternator whine with aftermarket headunit

Post by simroy24 » Thu Jan 17, 2019 4:56 pm

I had the same alternator whine issue after installing an aftermarket kenwood head unit. I was able to sort it by installing a couple of ground loop isolators. So far no issues and no engine noise through the speakers


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MikeFish
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Re: Alternator whine with aftermarket headunit

Post by MikeFish » Thu Jan 17, 2019 5:21 pm

I had it with my aftermarket amps with standard head unit and then with aftermarket head unit too. I tried everything including running an earth cable from amp to head unit to make sure there was no ground loop. In the end the only thing that fixed it was a ground loop isolator. I used it with some pretty decent kit and couldn't hear any loss in quality. In fact with the humming gone it was much improved.
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FrazerD
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Re: Alternator whine with aftermarket headunit

Post by FrazerD » Thu Jan 17, 2019 5:30 pm

Can I fit one of these even if I’m using a Bose harness? I’m assuming it just goes invetween one set of speaker phone cables to work?

Cheers :thumbs:

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MikeFish
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Re: Alternator whine with aftermarket headunit

Post by MikeFish » Thu Jan 17, 2019 7:31 pm

FrazerD wrote:
Thu Jan 17, 2019 5:30 pm
Can I fit one of these even if I’m using a Bose harness? I’m assuming it just goes invetween one set of speaker phone cables to work?

Cheers :thumbs:
They normally need to go between the head unit and amplifier. What do you mean by speaker phone cables?
My one was had RCA plugs / sockets to pug into the amplifier input.
RS6 Performance Panther Black KW Adjustable springs, Milltek Non-Res, exhaust valves disconnected & valve delete units fitted, TSW Bathurst, Eventuri intake

RS6 build thread: http://forum.rs246.com/viewtopic.php?f=76&t=119147

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FrazerD
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Re: Alternator whine with aftermarket headunit

Post by FrazerD » Thu Jan 17, 2019 8:24 pm

MikeFish wrote:
Thu Jan 17, 2019 7:31 pm
They normally need to go between the head unit and amplifier. What do you mean by speaker phone cables?
My one was had RCA plugs / sockets to pug into the amplifier input.
I meant phono cables, rca cables. My harness goes in between the Audi harness and my head unit with rca cables for speaker cables. So I would assume that they go to the amplifier but there are two sets, one for the front and one for the back. So do I just need to put it in one set?

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MikeFish
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Re: Alternator whine with aftermarket headunit

Post by MikeFish » Thu Jan 17, 2019 8:25 pm

Are you getting whine from front and back speakers? If so then you need one on both sets.
RS6 Performance Panther Black KW Adjustable springs, Milltek Non-Res, exhaust valves disconnected & valve delete units fitted, TSW Bathurst, Eventuri intake

RS6 build thread: http://forum.rs246.com/viewtopic.php?f=76&t=119147

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FrazerD
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Re: Alternator whine with aftermarket headunit

Post by FrazerD » Thu Jan 17, 2019 8:28 pm

MikeFish wrote:
Thu Jan 17, 2019 8:25 pm
Are you getting whine from front and back speakers? If so then you need one on both sets.
I’m not really sure to be honest but now I know I need one for both front or back. I’ll look into it more and do something about it. Thanks Mike :rocker:

Cheers :thumbs:

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Re: Alternator whine with aftermarket headunit

Post by jordanbutters » Thu Jan 17, 2019 9:10 pm

simroy24 wrote:
Thu Jan 17, 2019 4:56 pm
I had the same alternator whine issue after installing an aftermarket kenwood head unit. I was able to sort it by installing a couple of ground loop isolators. So far no issues and no engine noise through the speakers Image


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Did you try any alternative methods such as running new grounds?

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