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Discussion Starter · #1 · (Edited)
So I have a few parts in my other vehicles I’d like to get into the Metris, but rather than randomly throw parts I figured I would go ahead and do this one right.
First order of business is to measure the stock system in the stock van. I’ll measure from Driver and center of front row. I intend to tune for two seats, but understand that some may only want the Driver seat measurements.

I will be updating this post as time goes on with data put in the later posts.

Measurements from my setup (REW, UMIK-1, Onkyo DAC HA200 fed into the stock aux port, vehicle on accessory, all fans off).
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19600


Took measurements of the central speaker mounts up under the windshield, and according to the Focal documents (they publish exact dimensions for their stock fit speakers) the front center speakers are using a Mercedes SURROUND mount, NOT a center mount. I measured approximately 84.5mm edge to edge on the narrower set of holes with my pocket calipers (only model I had that would fit) and MB uses 7mm mounting posts giving me an approximate 91.5mm center to center. I can't measure the other dimensions because my calipers don't fit and my van didn't come with a speaker to remove. The normal speakers are 81.5mm, center are 61.2mm, and surround are 93.6mm. Audiotec Fischer sells a reasonably priced speaker for this location (S4MB-SUR) and Focal sells a nice Coaxial (ICR MBZ 100). The issue becomes the fact that they are at the center of the dash and without heavy processing would cause all kinds of havok with imagining. They do have what look to be decent mounts and some good air space behind them, however, so it may be worth giving it a shot as a midrange fill and dealing with the loss of imaging, especially for a stealth install. Since we don't have wiring building in a passive crossover feeding off of the tweeter wiring would be the best way to add them, though the distance between the components would further muddy imaging.

As of now it looks like the best way to use these will be to try running them as a sum of L+R in series across both. That should keep the volume fairly low, while not narrowing the stage TOO much, and let them open up the front. I may grab a set of the cheaper Audiotec Fischer speakers to try, or maybe pop for the Focal Coaxials.

For the stock mount tweeter, both Focal and Audiotec Fischer make a drop in, but they are only available off the shelf as part of a speaker set which includes their door speakers, which... we can't use in a stock/stealth install. If you'd like one (and maybe even the matching crossovers that those kits come with) eBay is your friend.

07SEP2020: I decided to throw the dice and grabbed a set of CDT Unity 8.0's (2" wide range speaker) on super sale, and a set of refurb ES-CRM-6iMK mid bass woofers (kevlar cone cast basket inverted magnet 6.5's). I'll run them active off my DSP and amp and see how it goes with the Unity's in the stock tweeter locations. It should also pull more of the staging up onto the dash; we shall see. I'll be comparing the JBL 670GTi, 670GTi + Unity 8, and the Unity 8 + 6iMK to see what I like the best. I get the feeling that the three way may be the winner, but I'll have to see.

10SEP2021: So I got my CDT Unity 8.0's in, and it looks like they will fit as a tweeter replacement if you are willing to cut the plastic cover. They would surface mount there, and the magnet fits perfectly in the tweeter mount.

Something interesting I found after pulling the tweeter is that it has a 4.7 uF cap, which means it's high passed to 11.3kHz... it barely plays anything.

My intention is to test the Unity 8.0's up top and see what frequency they like up there. Other reports have them crossing between 250 and 400 Hz, and they are reported to play up through 10kHz with no issues, falling off in that last octave. Ironically that means they would match the stock tweeter and fill in the midrange, if I can come up with a decent mount that leaves the stock tweeter in place. That's something I'm investigating, though I'll have to see how to make it work with the stock head unit.

Part of this project is to leave a record on what can be done reasonably and easily for owners without replacing the entire system, hence trying to make this work within certain confines.
 

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Discussion Starter · #3 ·
As of now nothing is decided. I have a JL MV700/5i amp/DSP and a set of JBL 670GTi components along with a JL 10TW3 sub in my other vehicle I'd like to move over. Honestly the stock head unit can stay if I'm fine with not having CarPlay; the JBL can do some really trick stuff like letting me use a portable DAC to feed in and then letting me isolate the head unit to certain speakers at a certain percentage of volume level (for bluetooth calls, etc), or whatever I want really. That's basically how my other vehicle is wired up.
 

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Discussion Starter · #4 ·
Oh, I did pull the doors and the speaker grill and the small pocket aft of it are all cast as a seperate piece, then plastic riveted in. It's entirely possible to build out a speaker pod there that could possibly take TWO 6.5" mid bass, or an entire three way component set. My two way is similarly installed in my truck and it sounds awesome to me.
 

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As of now nothing is decided. I have a JL MV700/5i amp/DSP and a set of JBL 670GTi components along with a JL 10TW3 sub in my other vehicle I'd like to move over. Honestly the stock head unit can stay if I'm fine with not having CarPlay; the JBL can do some really trick stuff like letting me use a portable DAC to feed in and then letting me isolate the head unit to certain speakers at a certain percentage of volume level (for bluetooth calls, etc), or whatever I want really. That's basically how my other vehicle is wired up.
Nice. The Kenwood unit I have does the ducking on things like GPS etc where you can select the speaker or speaks you want ducked. Really like like that and it's not something I have found in many head units.


19588
 

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Discussion Starter · #7 · (Edited)
19590


This is the full sweep, center mic. I'm still learning to read things, but this is really ugly I think. I used a high end input to this, and a calibrated mic.

What this is good for is if someone is adding an EQ and/or AMP to the stock headunit and speakers. I imagine the response for a new head unit would be significantly different.
 

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Discussion Starter · #11 ·
Honestly I'm not terribly surprised; it's not exactly a good system, and the van isn't exactly setup for decent acoustics.

Just means there's lots of low hanging fruit!
 

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Discussion Starter · #12 · (Edited)
So I played with the data a little more, because I had the thought that I should be looking at this like I do RF stuff (I'm a HAM). So I looked for the floor to see if any of this is environmental noise. I ran everything off of battery, and the vehicle was on accessory with the ventilation off. It was silent as far as I could hear.

This is a 2s waterfall, and as you can see those peaks are reverb, not environment. This vehicle reverbs like noone's business, and I have the back full of kid stuff (most of that soft stuff that should dampen).
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Here's the SPL graph of the two center runs:
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Not a surprise, but the stock system is garbage, to not put too fine a point on it. However, knowing where we are starting from lets me plan what should be addressed.

One of the things I was looking for was to figure out where the stock system plays each speaker. It looks like they cross between 1k and 2k, which is where you'd expect. We can also see that the woofer is being pushed all the way down and really doesn't like it. It's response shows some power down below that 150Hz dip, but in reality I'd probably want to keep it above that as it shows much smoother performance there. It has consistent performance down to about 38Hz but below that every run was off by several db. The other thing to note is that this system is heavily bass biased, unsurprisingly.
 

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Discussion Starter · #16 ·
I decided to throw the dice and grabbed a set of CDT Unity 8.0's (2" wide range speaker) on super sale, and a set of refurb ES-CRM-6iMK mid bass woofers (kevlar cone cast basket inverted magnet 6.5's). I'll run them active off my DSP and amp and see how it goes with the Unity's in the stock tweeter locations. It should also pull more of the staging up onto the dash; we shall see. I'll be comparing the JBL 670GTi, 670GTi + Unity 8, and the Unity 8 + 6iMK to see what I like the best. I get the feeling that the three way may be the winner, but I'll have to see.
 

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Discussion Starter · #17 ·
So I got my CDT Unity 8.0's in, and it looks like they will fit as a tweeter replacement if you are willing to cut the plastic cover. They would surface mount there, and the magnet fits perfectly in the tweeter mount.

Something interesting I found after pulling the tweeter is that it has a 4.7 uF cap, which means it's high passed to 11.3kHz... it barely plays anything.

My intention is to test the Unity 8.0's up top and see what frequency they like up there. Other reports have them crossing between 250 and 400 Hz, and they are reported to play up through 10kHz with no issues, falling off in that last octave. Ironically that means they would match the stock tweeter and fill in the midrange, if I can come up with a decent mount that leaves the stock tweeter in place. That's something I'm investigating, though I'll have to see how to make it work with the stock head unit.

Part of this project is to leave a record on what can be done reasonably and easily for owners without replacing the entire system, hence trying to make this work within certain confines.
 

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Discussion Starter · #18 ·
No response numbers yet, but the Unity 8.0’s are in and WHOA did they transform even the stock stereo. Not running any caps right now, so they are full range and it’s amazing how low they go. They really are wide range. I’ll be cutting the plastic panels and applying felt to dampen the reflections. Right now the magnets are friction fit and they are running free air, which isn’t ideal.
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Discussion Starter · #19 ·
I haven't updated this because life got in the way and I've had no changes. The Unity 8.0's are rocking up top, but I have a new head unit on order and then I'll be swapping in my JBL 670 GTi's and JL 10" sub with a JL DSP/AMP and start playing with some real tuning.

Hoping to have some solid updates on this stuff over the next few months since my life seems to be settling back down.
 
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