US I4 (400hp) has fake engine noise pumped through speakers

[Kaz]

Good morning, I’m fixin to start disassembling everything this morning. After playing around with the gas pedal, broom stick and putting my ear next to the rear speaker I can hear the fake noise. Your thread just saved me a ton of frustration, cursing and breaking things. Thanks again
I’m not done searching the forum, but so far I haven’t found wiring on the tweeters. Do you by chance know the colors for +- on the door speakers? I’m going to tap into those for the tweeters.

I don't unfortunately but there are several threads like this that might more detail. https://www.emiraforum.com/threads/initial-results-after-adding-tweeters.5742/

 

[Ryan_929]

I don't unfortunately but there are several threads like this that might more detail. https://www.emiraforum.com/threads/initial-results-after-adding-tweeters.5742/

Got distracted with errands today but had enough time to fix the engine noise and wire the sub. It sounds a million times better with just the sub. I’m gonna tackle the tweeters tomorrow morning. I found the thread with the wire colors.

 

[F1 SML8R]

@Ryan_929 there's a great video on the "adding a sub" thread that is really good at showing all of the dismantling and access. if you do open up the passenger rear area where the sub is, see if you can snap a pic of the actual wire harness with the green wire you snipped from a distance that makes it obvious which harness it is and it's location.

After watching the video, the access to this spot is really easy to get to, but the wiring harness wasn't obvious given there are a few back there that plug into the black sub. Thanks in advance if you are able to get to it and good luck on the tweeter install.

 

[Ryan_929]

So I looked backed through my photos and realized the video I thought I was recording wasn’t actually recording so all I have is the initial portion of taking the trim off. I tried to screen shot the best I could with a yellow arrow pointing to the wire bundle. I’ll take the trim off and get a better pic today. It’s super easy to get to and should only take about five minutes. Pull the corner trim from the right side (passenger for me). The wire harness you need is the far left bundle of wires that connects into the bottom of the black amp. There are three sets of wiring bundles the connect to the black amp. Cut back the electrical tape on the left bundle and it’ll be the green (with a thin yellow stripe) wire. Wrapped the exposed wire ends and that was it.

 

[F1 SML8R]

Agree, I saw the access was a quick pop off of that side panel in the other video I referenced. Thanks for providing this pic. I think I can see which one it is now with this pic as a point of ref. Appreciate it brother.

 

[Kaz]

View attachment 63687So I looked backed through my photos and realized the video I thought I was recording wasn’t actually recording so all I have is the initial portion of taking the trim off. I tried to screen shot the best I could with a yellow arrow pointing to the wire bundle. I’ll take the trim off and get a better pic today. It’s super easy to get to and should only take about five minutes. Pull the corner trim from the right side (passenger for me). The wire harness you need is the far left bundle of wires that connects into the bottom of the black amp. There are three sets of wiring bundles the connect to the black amp. Cut back the electrical tape on the left bundle and it’ll be the green (with a thin yellow stripe) wire. Wrapped the exposed wire ends and that was it.

This is SUPER simple clear view...if I only had a time machine and zipped forward to see this lol

 

[Ryan_929]

Here’s a better view of the wire.

 

[F1 SML8R]

@Ryan_929 Awesome, thank you!

 

[Lotus F1]

Are you guys sure that you were just not disconnecting the auto volume level of the stereo entertainment system.

 

[Kaz]

Are you guys sure that you were just not disconnecting the auto volume level of the stereo entertainment system.

This wire is the rpm wire to generate the AMG Real Performance Sound, not related to the volume level.

 

[Lotus F1]

Okay has this been verified

 

[Kaz]

Okay has this been verified

yep and it's pretty obvious when you get rid of the fake noise, but yes verified the diagnostics initially came from Lotus service on where to find the ECM and what it was putting out, then my audio shop ran tests on all the wires and found the rpm signal going into the dsp (the only wire that had variable voltage as they were testing the throttle). And you've seen the video I posted right? I don't know how to demonstrate any clearer and now anytime you hear an AMG M139 you'll recognize the fake sounds.

 

[Ryan_929]

Kaz went through a much better verification process than me. I just put my ear next to the rear speaker while giving it gas; before and after cutting the wire. Sound was there before and no sound after. Both times the radio was off.

 

[Medic518]

DONE. Easy access, quick work, and soooo much better!! Not over the top great, still needs some fine tuning and testing, but the bass distortion is remarkably less, even at volume.

I added a bullet connector just in case I need to reconnect. Also, I did run into a small oddity, that eventually resolved itself. For some odd reason, post surgery, after moving the Emira from the garage out into a bright sunny day, the dash stayed dim for a long time - almost like it didn't detect the change in the light outside, which made it really difficult to see the dash and center console. Not sure if it was at all related, just something I observed and again it resolved itself.

 

[Medic518]

OK, noticed something else - maybe someone knows why - but I noticed with the windows down, the bass is more pronounced. To test, I had the windows down, turned up the volume and then closed the windows. The effect was like the bass in the system turned almost completely off. Put the windows back down, with the same song playing, and bam! bass is back.. Like the audio system is aware when the windows are up or down.

I am sure this is also unrelated to the fix, but am wondering if it may have been happening all along but is now noticeable? Also if it may have to do with the open air sub in some way?

 

[Kaz]

OK, noticed something else - maybe someone knows why - but I noticed with the windows down, the bass is more pronounced. To test, I had the windows down, turned up the volume and then closed the windows. The effect was like the bass in the system turned almost completely off. Put the windows back down, with the same song playing, and bam! bass is back.. Like the audio system is aware when the windows are up or down.

I am sure this is also unrelated to the fix, but am wondering if it may have been happening all along but is now noticeable? Also if it may have to do with the open air sub in some way?

It's probably the design of the open air sub and its relation to the interior air volume - I can't test this because I removed all the stock speakers from the car but you're probably just being able to be more critical about what you are hearing now that all that noise is gone. I vaguely recall some discussion about the free air sub in the audio/electronics area

 

[Ryan_929]

OK, noticed something else - maybe someone knows why - but I noticed with the windows down, the bass is more pronounced. To test, I had the windows down, turned up the volume and then closed the windows. The effect was like the bass in the system turned almost completely off. Put the windows back down, with the same song playing, and bam! bass is back.. Like the audio system is aware when the windows are up or down.

I am sure this is also unrelated to the fix, but am wondering if it may have been happening all along but is now noticeable? Also if it may have to do with the open air sub in some way?

I’m a rookie with car audio installs so this might be a useless response, but…
Once I installed the sub in my Hummer I could definitely notice a difference in the bass when I crack the windows open opposed to having them closed. It seems to have more bass with the windows open. I think it might have to do with the air space inside the cabin of the car. A ported box hits deeper than a sealed box but sacrifices audio quality. I think it could be the same concept.