Pseudomaniac

With the power already run to the trunk, half the battle is already won.
Doing a bit of investigation the amplifier APPEARS to be on the drivers side trunk well, behind the carpeting. Not easily accessible with all the other convertible top bits in place.

I have a small sub/amp combo and a line level to RCA converter.

On the cabriolet, the subwoofer APPEARS to be the speaker between the rear seats at the base.

Thinking I had it all figured out, I pulled what I presumed was the sub connector and spliced it, but it must be something else. Some microphone feedback to the amp maybe?

Anyone know what pair of wires I can splice to get the sub output? Diving any deeper into the car is MAJOR surgery and contortion.



This plugged straight up into something behind the grate, and you can literally see the back of the sub right here. It's a gray / gray/yellow pair.


It looks like this silver box on the left may be some sort of fiber network control device. Not sure if it's stereo related or not.

I'm guessing some of the loom there has to be stereo/speaker leads, if the amp is in the rear, as they lead that way. Would seem finding the pair that goes to the sub would be easy, but striking out.

Also would be very helpful in the rear fuse panel to know where to tap a remote line.

Thanks in advance!

Pseudomaniac

When the back doesn't work, try the front....

I still need help with a remote power source, but have the speaker leads figured out.



Unplugged the sub connector. It's in the front. To get to it, gently remove the rubber bottom from the front cupholder to reveal a torx screw. Remove the screw. Pull up from under the outside front corners of the seat on each side and you'll hear a "pop" and feel them release.


The little plastic shroud under the subwoofer pulls straight out and lets you get your hands on things.


The subwoofer is stereo fed. There is a Purple pair where one has a brown stripe, and a Green pair where there is a brown with green stripe. These are the amplified speaker lead outputs.

SteveMcQueen

Yeah, reviving this super old thread!

I just picked up a used 2014 E350 (a207) Cab and I want to take on a similar project.

From what I've seen in WIS/EPC so far, the Cab didn't have a subwoofer so I'd like to add one. If there is one, I want to upgrade it.

The HK L7 sound system isn't the worst or best I've ever had. I think with a better/added subwoofer it'll be acceptable.

Did you ever finish this project?

Pseudomaniac

I did. You can tie into the battery in the trunk, and get remote from the fuse box. I put a very slim box and short throw 10 in the trunk and it adds massive bass, even with the top down. Really wakes up the bottom end.

SteveMcQueen

Sounds good. What model sub did you use? Any other details on wiring, especially where you tapped in to the existing system for audio signals would be much appreciated.

What did the silver box end up being?

Pseudomaniac

The wiring is in pictures above. Don’t need a silver box. If you put line level taps on the leads I shows above, you can get your speaker level inputs for a sub amp.

i used a pioneer TS-SWX2502 boxed short throw.
it fits under the open convertible top way back in the trunk and disappears, and I have an old pioneer 1000 watt class D amp bolted to the top. It’s cheap and it sounds good enough.

SteveMcQueen

Thanks for the info!

SteveMcQueen

What did you end up using for your amp "remote on" wire?

The amp I'm using (AudioControl ACM-1.300) has a remote turn on connection, but also has a "GTO" feature where it senses the speaker-level signals and turns on.

I'd LIKE to have it turn on only when the other audio components are active, mainly the head unit. There is a "MOST Wake-up" wire that I'd like to tap in near the factory amp in the trunk area but I'm uncertain as to it's electrical characteristics and behavior.

The alternative is use a "add-a-circuit" fuse tap on the rear fuse/SAM module on an ignition switched circuit. If you did this (and your posts suggest you did) which fuse position did you use, and did it work well?

SteveMcQueen

Making progress!

vintageaxeman

Hi fellow Merc enthusiasts. I have a 2011 A207 cabriolet with the Comand and HK system.
I've read all the above and I still don't know where the HK subwoofer actually is.
Mine is blown, and I can hear the cone flapping. I don't want to upgrade it, I just want to remove it and replace it with one from a breaker's yard.
So please can somebody help me?
To get to the subwoofer, do I go in through the rear seats or through the boot? It LOOKS to me as though I have to remove the seats, but I'm not sure how to.
Any help would be wonderful here, and if possible, does anyone actually have the pdf of the whole subwoofer removal and replacement process?

Also, from the screenshot here, how do I remove the silver mesh grille with the 'Harmon Kardon' badge?


Thank you!