The doors are all passive, one wire coming from the amp in the trunk to each. We used the Focal crossovers in the front doors. We took a channel off the Prima to each door, bridged two more channels to each footwell sub for a total of 8 channels and then the sub out to the sub amp and trunk box. We left the center and rear deck surrounds alone.

I'm using the stock Burmester 2 ways in the rear doors. Ok for rear fill.

 

How do you open the Focal tweeters? I don't want to cut them.

 

Not sure I understand the question. Open them in what sense?

 

I want to open the enclosure so that it can fit into the Mercedes tweeter holder.

edit: I found the small plastic tool which opens the tweeter from the top. Installed door #1

 

Got it, you need to remove that decorative outer bezel.

 

Now I'm struggling to find a spot for the crossover. Where did you put it?

 

So, @Mike5215 , is it better to go without the Burmester and just get the stock one and upgrade from there or is that too much work for the $$ involved.

 

I'll ask the shop. It was already under the Hushmat when I saw the door.

 

I'd still get the Burmester. You get an extra sub, 4 tweeters, a center channel and two surrounds. Plus the Audio 20 sounds pretty cheap and thin out of the box, whereas the Burmester , while not ideal, is still very listenable modded or not.

 

Well, I installed the Focals and I must say that I'm not happy. It didn't fix the total sound experience. If anything, the factory sub sounds even worse now when compared to the crisp Focals. I'm guessing it's the factory amp that has a crossover at probably 500Hz so the bass would cover for the sh...y speakers in the doors. Does anyone know if there's a way to change the crossover point? (yeah, I know, get a new amp)

 

Yeah, the Focal Mids don't sound much different than the stock Mids. The tweets are nicer though. If they're too bright, make sure the position switch on the crossover is set to "Hi". That's actually low boost, for when the speakers are mounted high on the doors.

The only way to modify the factory EQ is to kill it with a DSP and then rebuild it, and it helps to get the lows out of the front subs and handed off to a separate sub in the trunk. Then you can band pass them to play mostly tight mid bass like a conventional woofer.

Given the price of the Focals I'd recommend leaving the speakers stock and putting that money on the Prima unit. Much more bang for the buck even if you have to wait to add the trunk sub.

 

Mine were set to "flat". Changed it to "high" and it's much more balanced now. Thanks for the tip. I thought "high" meant higher volume. Strange naming...

 

Me too. Lo presumes they're low in the door and need to cut through the seat upholstery.

 

I had just the opposite opinion. I thought the stereo in the C300 loaner sounded awful. I'm not super impressed with the Burmester either but it's OK and I can easily live with it..

 

Yeah, there's not much to the Audio 20. Four 4" mid range door speakers and one sub. The Burmester at least gives you something to work with.

 

Has anyone replaced the sub? Burmester or Audio20. Is it something I could do myself?

 

You could, but it's an unusual form factor. Very shallow mount. Probably easier to add a sub box in the trunk and pull signal from the amp in the trunk.

 

I have an Audio20, I don't think it has an amp in the trunk

 

Do you know what the depth of the 8" subs are? Wondering if I could replace them with something like a Dynaudio 8" mid-bass driver for an active 3-way setup - this speaker has a 3.75" mounting depth...

 

Haven't had my hands on them, but I think you'd be okay at that depth. Not sure how big an improvement they'd be without some way to fix the EQ.

 

Right - this would be a similar setup to what you did except upgrading the 8" stock woofers...

 

I'd do the Prima (or similar) first to see how the woofers respond to the tune. Hard to know what their deficiency is before-hand, and without knowing the deficiency you can't know which problems the new woofers are supposed to solve.

As a stand alone mid-bass driver, bi amped and fully tuned, the stock footwell speakers are solid performers. I'd have replaced them if they weren't, but I'd suggest at least listening to them before deciding.

We had originally planned to go 3 way active up front however the way the fronts are wired on the factory amp as passive two way with a single wire from the trunk would have required drilling into the front door shells. We decided to go two way active up front (woofer & mid/tweet) and use some band pass filtering and EQ for control. That also freed up two channels on the Prima that we bridged to double up power on the footwell subs.

 

So you just used the stock passive crossover with the new mids and tweets?

 

If I hadn't had the Focals on hand from a previous car (which have their own crossovers)I would have done exactly that. I mean, there's only so much you can expect out a 4" two way anyway.

Those Focals were $750 when I bought them two years ago, and aside from the tweeters sounding marginally cleaner and sweeter than stock, you'd have a hard time telling them apart from stock. I made the mistake of doing speakers first on my S550, which changed nothing, and then having to do the Prima.

I'd leave the cabin speakers alone, add the sub box and let the DSP do whatever correction the system needs. You can always go back in and upgrade speakers if you're not happy with how they're responding to the tune.

 

Maybe MY17s will have better materials?? One can hope. I have a pretty loaded out AMG C63 S coupe on order, and it would suck paying $90+K for a car with a crappy stereo.