Viper98912

Has anyone replaced the stock Harmon Kardon subwoofer in their C55 with any luck? Here's my thoughts:

Current issues -
1) The back deck rattles due to the sub's location depending on the frequency played. Haven't been able to pinpoint the rattle location since it seems to be the whole deck, especially with the sub's mounting. Very frequency specific.
2) Really low freq's are non-existant, but I wonder if this is the sub's lack or the amp's eq crossover points for the "cheap" speakers
3) As volume increases, the stock amp's sub power decreases.

Idea - disconnect the stock sub, use this output as a high level input to an external amp (maybe 100-200w) and use a 10" aftermarket sub in a sealed box. Or Infinity Basslink, Bazooka tube, or something similar.

I do NOT want to do an indepth system, with a Cleansweep, new car wiring, etc. Just the basics for a sub and amp install (which I've done many times before). I just don't feel like messing a lot with the stock system and fiber.

Possible solutions and problems:
1) Getting everything after the stock amp:
- Problem - the amp's eq and crossover points might give me the same sound I have now. Also, sub volume may decrease in the same way it does now. Remedy to the volume issue would be a remote bass knob. Crossover points could still be an issue.
2) Car's noise level mic:
- Problem - it might think the new bass is noise and decrease or muffle the sub's output from the stock amp. If so, then all that work would have been for nothing. But, this is why using the stock amp's sub output might work (since it's not an external sound input that it doesn't know about), but then again might not.

Has anyone done any simple setups on their C55's HK system? Listening to ideas.....

Martinsvi

I initially did exactly what you are describing. I disconnected the sub, took that set of leads and drove a Alpine MRP-500 mono sub amp($200) and built a small sealed enclosure for 2 older Soundstream 8" Subs(from back in the old days when soundstream was a good company) and built me a new subwoofer system. The enlosure didnt take up much of the trunk at all and is good clean tight bass. I would remove the sub excpet it is a pain to remove the rear deck on the car. I had a total of $300 in the whole project as I had the subs already so I just had to buy some mdf, carpet and a few othe odd bits along with the amp wire kit. I also had an old pac High to low level convertor that custs on with signall applied so I didnt have to go to the head unit to try and steal signalls. Total time to accomplish was about 4 hours.

91RS

Yeah, I've got similar issues as you do. I think a few other speakers are blown though. I kept all of my system from the old car, but the old car didn't have the HK system. I though about taking a look at the HK amp when I did my rearview camera install, but I ended up not taking anything out on that side so I didn't bother. The HK system sounds decent I guess, but maybe more good bass will help it at bit.

loudandheard

The weak point in the system are not the speakers, but the amp. The speakers are actually decent, but the power is just not clean or very powerful.

Martinsvi

I will have to agree here. If I was going to start over I would get a processor off of the amp and then go to town. The sad thing is you have to use your old speakers as mounting adapters for the new ones. I put Hertz High energys' in my car and wished I could have had some old blown speakers to use for that.
My main requirement was to ruse the old head unit.
I see there is a new player in the fibre optic game by the name of motus lab. They make a processor that goes in place of the amp and then you can use whatever amplification you wish.
Alpine has redesigned their imprint processor so that can be a good alternate.

Viper98912

91rs, I have to agree, the HK system sounds decent "enough". I don't know, I haven't fully decided if I can live with just "enough", coming from a nice system previously.

Martin, so how did you like your new bass output with the rest of the stock system?
Did you get much lower freqs with your new subs, aka is the lack of low bass response coming from the stock sub or from the stock amp eq?
And did you have any problems with the mic? Did you have to disconnect it?

91RS

I've never heard of the processor thing, so that would connect up to the fiber optic cables and then put out "normal" connections for an aftermarket amp? Hmm. I agree Viper, good enough may not be good enough for very long. My very simple system I had before sounded excellent. I had an Infinity 475 amp and Kappa speakers. I left the door tweeters to run off the radio's power.

Martinsvi

I have not disconnected the mic yet. It helps right now with increasing the output while driving so it hasnt been a issue. I have for me plenty of bass. I prefer the bass to be tight and controlled. If it cannot go super low that is ok as long as it is controlled where it can go. I wasnt totally dissatisfied with the bass of the stock system, I just needed a little more bass. I listen to jazz and rock so I dont listen to "boom music" , but I am critical of the sound quality. So far every upgrade I have performed I have been satisfied with.
I believe though if you want alot more thump in your trunk then yu will need to go with something like Digital Design. They make a nice sub preloaded in an enclosure and all you need is the amp. The price is pretty good and they are quite efficient and can play really loud.

Martinsvi

There are alot of changes going on in the fibre optic side of car audio. New names are coming out with stuff that is going to give us more options.
The stock head unit in these cars isnt bad at all. Far better than the old days of the becker stereos and the fader in the center console.
The most ring(fibre) gives alot of flexibility to the system and is very noise immune. So between companies like mobridge, motus lab, audison, and a few others we will eventually have as many options as any other car. Especially as more mfg's change over to most technology for the car.

Motus labs processor as I can tell is going in place of the h/k am and is giving you up o 8 channels of output. You can then with a laptop and a service tool configure and equalize the car to suit your taste. Once this is done you can use the bass/treble controls on the head unit for occassional changes as you do now. It looks to be interesting times in the ccar audio world again.

SilverBulletAMG

I don't remember if the back deck on the 55 is the same as the 32, but on mine, I get a frequency specific rattle coming from the latch where the first aid kit is stored (back passengers side). Other than placing something heavy on top of it, I haven't found a cure for the rattle. I'm running a 12" Type R with an Apline M650 and gave up on the stock setup alone.
For your setup you would be good with any amp that has speaker input leads. Then grab a decent 10" (or 12") sub and you're set. Adding an amp and sub to the system is pretty straight forward. Replacing the head unit and the rest of the speakers, not so much.

Viper98912

Really what I should do is leave it alone

Martin, that info you have about the fiber optic systems is interesting. I just wonder how it's going to process some of the stuff though, since now there is so much car data going through fiber as well, aside from just the sound.

You can buy an Infinity basslink for $179 shipped off Amazon, which is really a great price IMO. You can't beat that for what it does.

At the same time, coming from a small(er) trunk in my past car with a box, I thought the trunk in the C was ginormous. I took some measurements though and realize it's not that big! I guess that's the false view I have from now on since I've never really had a full trunk.

So did anyone notice any lack of low-bass freq when tapping after the stock amp? (internal eq setup of the amp). I wonder how much power the stock amp gives....aka replacing the stock sub with a new lower power / high efficiency DVC sub with a wider freq range and put it in a sealed or ported box in the trunk. I wonder if it would have enough power though, since the bass would no longer come directly into the cabin (the stock amp wouldn't be able to provide enough power). Also negates the fact that I wouldn't have a remote bass knob to up the bass when the car decides to turn it down. I don't understand why MB didn't put a subwoofer +/- function in the bass/treble settings on the stock radio, as almost every other car manufacturer (and every aftermarket manuf) does nowadays.

When I first got the car I also looked into replacing the stock sub with an aftermarket thin sub, yet realized it wouldn't work since the bottom of the sub (trunk side) is actually the rear deck sheetmetal. I've never seen it done like that before, all I've seen before was just holes in the sheetmetal. So depth wise, you'll never fit anything but the stocker there in between the rear deck and rear panel.

Another thing I'm eyeing is that open area on the driver side of the trunk.....A nice small fiberglass box covered in black carpet would probably match very nicely there and take up no space....

Viper98912

And something else I've been kicking around as well, is that the stock sub is free-air (or at least, someone made the decision to use it as free air). I wonder what would happen if we create a sealed air volume below the sub? It wouldn't be completely sealed since there's a foam gap that the sub mounts on to the rear sheetmetal deck, but it might change the sound, hopefully for the better.

Martinsvi

Remeber that the most ring(fibre optic) is transmitting alot of data including audio. Audio is probably the easiest thing it does. The devices are setup where they use the data that is important to them and disregards the other data packets as they dont address what that device is setup for.
Think of it as a standard network in a building, there is taffice on the line all the time but the computer your at only addresses the datas it needs.

The sub that is in it isnt that bad as long as you arent listening at high volume. It is effecient and space wise takes up little. It is free air which helps it, but also hurts it. If more bass volume or higher spl's across the spectrum is what your after then more power is required. Mercedes has the volume being controlled by the mic for a couple of reasons, 1 is to increase volume as road noise comes up to overcome the noise and keep a constant volume, the second is to reduce the volume when you are reaching the limits of the amplifiers output. Or to keep the amplifier from clipping. If you use a different processor to either augment or replace the existing poweramp then as more power is needed for more volume then it wont be an issue as it isnt in the circuit to do it or the amp wont be clipping while feeding the new processor as it only wants the signal.
I dont have an infinte amount of time or resources to put to this project but as I get time I like to do upgrades to the system and get it closer to what I think it should be.

First thing I did was install the alpine sub amp and a new sub box in the trunk. I lost very little trunk space(less than a foot)and it was all up front at the back of the rear seat. With those 2 8" subs I have been more than happy.
The next thing I did was replace the door speakers with Hertz High Energy components in the front and coaxs in the back. I will live with this setup for a while before I make the next change to a different processor. I have a line on the new alpine imprint processor and a pqx5 amplifier. If this works out I will give you guys an update to the effects. If this doesnt work out I will look into the motus lab piece. Problem there is it is new and they dont have much info on pricing or availablity. Another option is the audison piece either the da1000(price and availability issue) or a BIT1. Either one of these is going to be a pricey piece, but so is the car we drive.

91RS

That one from Motus Labs looks really nice. I can't find a place online to buy any of them though. I wonder how much any of those products will cost. That is definately the route I would like to take unless that stuff costs a small fortune since external amps will still be needed to go with it to power the speakers.

Martinsvi

Thats the rub right now. The product is there but other than the web site and a few dealers, virtually nothing is known about them. I dont mind spending the money if I know where to get it and I can find out if it is worth it.

ruben65

So are other C55 owners hearing the same rattle in the rear deck? I thought it was just me, I have noticed the rattle in the back at higher volumes and certain frequency's its driving me nuts. My last mercedes had the Bose system and the sub was fine in it no rattles and plenty of bass.

What if you replace the HK amp and sub with the Bose AMP and sub from the C32? would that work in the car? should take up the same space and use the same mounting right?

I also hear rattle in my drivers door speaker cant tell if its the speaker or something on the door, anyone else having that issue?

Martinsvi

You cannot replace the h/k amp with a bose. the h/k is fibre optic controlled(most ring) the bose was copper wired.

I never had a rattle in my back deck, I was just looking for some extra bass that wa a little better controlled.

I am not haveing any rattles or buzzing in any of my doors.

billapex

Mine has what I assumed was a blown sub (certainly sounds like it), but it looks physically fine, from what I can see. However, all this talk makes me wonder if it's the shelf rattling.

Is there any definitive way to test whether the speaker is actually blown or if it's the shelf?

Bill

RW C55

The buzz coming from driver's door is usually from the loose trunk opener button. I folded a small piece of paper thick enough to fill the gap between the button and the frame, and it fixed the buzzing on the driver door.

Viper98912

I also have a drivers door buzz that I wasn't sure if it was the speaker or something rattling in the door. Looks like I'll have to look at this trunk button and cross my fingers

As for the sub rattle, it most definitely seems to be (for me) the shelf (or something of large size, maybe the sunshade), not the sub itself nor the sub psuedo-grill. It's VERY frequency specific, not just volume specific. I've got a few tracks that have a kick drum at the exact frequency, and it rattles even when the volume is almost silent. Yet I can turn it up with other tracks at a differenet bass frequency and I get little to no rattle. I still haven't found the solution to this yet, regardless of pushing the shelf around.

RW C55

I use to have the subs rattle problem as well, and i was pretty sure it came from the deck (the shelf). Weird tho it went away itself...

cldriver

Have the rear sub buzz as well, its the shelf/speaker grille and not the sub itself.

question, how did you guys route the amp power wire? where can you get thru firewall, assuming you are running a direct line to the battery up front.

ruben65

Tested it out today, it was the trunk button and the grill above the sub on the rear deck, i turned everything up and held each piece and the noise went away. but i also found another rattle under the car, i think its the exhaust heat shield, i'll climb under another day to take a look.

thanks for the recommendations RW C55, that seemed to work, im working on a different fix to solve issue and will let you know.

Martinsvi

I ran a 8 guage power cable to the battery from the trunk down the passenger side of the car. Up at the firewall on the passenger side there is a weatherproof pass0thru for the cable, it is easier to run though if you have 2 people..1 inside and 1 up front when going to the battery.

91RS

[QUOTE=Martinsvi;3896952]I ran a 8 guage pow