Custom trunk sound system in process!
Thread Starter
Senior Member
Joined: Apr 2008
Posts: 275
Likes: 1
From: San Francisco
C300
Custom trunk sound system in process!
Hey guys,
Just dropped of my car to a friends shop to have a custom sound system put in. I'll be removing the spare tire and having a fiberglass box built to utilize the space of where the tire was. The top portion will have the padded leather look with the amp encased in the fiberglass but removable through a slot for adjustments. I grew up with the owner since middle school back in the day and he also drives an E55. His opinion was not to change out the factory speakers if you have the HK system as they sound much better then most aftermarket speakers.
I reused my old subs/amp which are:
2x 12" w3v2 JL Audio subs
1x 500w Mono 1 channel JL Slash amp bridged.
If the trunk rattles they will dynomat the trunk for me free of charge.
For the custom box + audio cables/wires + labor they only charged me $350 + a pack of smokes.
I'll have pictures up as soon as its finished. Hopefully if I have time maybe some in process shots as well.
Stay tuned!
Just dropped of my car to a friends shop to have a custom sound system put in. I'll be removing the spare tire and having a fiberglass box built to utilize the space of where the tire was. The top portion will have the padded leather look with the amp encased in the fiberglass but removable through a slot for adjustments. I grew up with the owner since middle school back in the day and he also drives an E55. His opinion was not to change out the factory speakers if you have the HK system as they sound much better then most aftermarket speakers.
I reused my old subs/amp which are:
2x 12" w3v2 JL Audio subs
1x 500w Mono 1 channel JL Slash amp bridged.
If the trunk rattles they will dynomat the trunk for me free of charge.
For the custom box + audio cables/wires + labor they only charged me $350 + a pack of smokes.
I'll have pictures up as soon as its finished. Hopefully if I have time maybe some in process shots as well.
Stay tuned!
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Joined: Mar 2009
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From: UCF area Orlando/West Palm Beach FL.
c350coupe, Gencoupe R-spec
looking forward to seeing the pics, i was thinking of doing a set up like this or replacing the HK sub with a JL sub. I just sold my digital design setup and im already missing my bass.
Thread Starter
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Joined: Apr 2008
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From: San Francisco
C300
Yea I talked to them about replacing my stock HK Sub and just having a free air setup using the factory sub location. They said they don't recommend it...and the only way to fit a larger sub was to cut away at the metal/panels and create brackets which would eventually rattle. My biggest issue was just a balanced system that didn't rattle and still let me keep my trunk space. I don't do a lot of traveling and only drive to/from work so if I were to blow a tire I could have my spare brought to me easily.
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Joined: Mar 2009
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From: UCF area Orlando/West Palm Beach FL.
c350coupe, Gencoupe R-spec
yeaa my shop also told me the same thing with replacing the HK sub. suck bc it would be a really nice stealth set up. rattling sucks. i had to tape down my license plate frame to cut out rattling lol
Thread Starter
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Joined: Apr 2008
Posts: 275
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From: San Francisco
C300
Lol they make this double sided rubber license plate gasket/grommet that you stick behind your license plate and to the car. It gets rid of all license plate rattle. I'm more worried about interior rattle which is just to hard to pin point what exactly is rattling haha.
Car should be done Friday. I might be heading there on my lunch break to snap some shots of the process.
Car should be done Friday. I might be heading there on my lunch break to snap some shots of the process.
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From: NNJ
'11 C350 '13 F150 lariat
I have a custom system in my 2011 and I did a sub/amp upgrade in the HK in my 2008. The biggest rattle is the trunk vent inside the trunk on both quarters. They vent into the quarter panels and they have 3 plastic flaps that freely open and vent the trunk. Thats 80% of the noise, dynamat or second skin right over the whole panel, and then remove the top of the trunk liner (where the spoiler sits) and dynamat that. Use a gasket on the plate and in between the frame if you have one and its almost rattle free. I didnt do my 2008 but did my new car and its rattle free. I did all JL component speakers and 2 amps and a cleansweep, the only non JL is the infinity kappa 2ways I used in the rear doors. System pounds, and I just got a VIM yesterday and 10 DVDs from dvdmixtape.com so I can watch my music too......its the boooooomb
Thread Starter
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Joined: Apr 2008
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From: San Francisco
C300
Bro that's perfect! Thanks I'll call the shop and have them dynomat the area's you suggested while the trunks torn apart. Any other spots you know of? I don't mind a little harmless rattle but at the same time I'd much rather have it done right. Hopefully all goes well and I won't have to worry. I feel a bit bad taking advantage of a free dynomat job lol. Initially they said they'd mat it only if it did rattle. Maybe I should just wait and see...
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From: NNJ
'11 C350 '13 F150 lariat
bro I wouldnt post the info without first hand experience. I have a system in everything I own, even my bobcat skidsteer and my boat LOL, no joke I got subs in my boat. Im on my second W204 and had systems in both, this new one is fully custom except the head unit. Inside the car you dont really hear the rattles cause the bass hides it, BUT outside the car its bad in stock form. In 09 I took the white 350 I had to a euro show down the jersey shore one night and guys were pumping their systems. People checking the ride out (they were rare then especially modified) were like lets hear the system when they see the subs. I stood outside the car in back of it and I couldnt beleive the rattles, like a cheap honda w a pepboys system, I was almost embarassed. That weekend I spent tearing the trunk liner out and I taped the vents shut w foil A/C tape and felt lined the trunk, dynamat was too much for me then. In my new one I did the trunk same time I did the subs w dynamat, and my bass sounds better in the car even. I also took out the foam on the upper rear deck and it let the flow into the cabin better. Now I got massaging seats like an S class LOL
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Thread Starter
Senior Member
Joined: Apr 2008
Posts: 275
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From: San Francisco
C300
lolo @ pepboys system hahaha.
Yea this will be my 2nd custom trunk. First was in a old lexus sc300. Surprisingly the SC300 had zero rattle. I can only think it's because the car itself was like a tank. I called the shop and told them to test the system before putting the trunk back together. Right now the box is being dried and the wires are already laid out. I'm hoping for it to be done tomorrow but don't want to rush them. I'll be stopping by sometime tomorrow so they can test the sound and decide if everything is fine. I'm not going to be blasting my music very much. It's mainly just for myself.
On a side note how do you like the cleansweep?
Yea this will be my 2nd custom trunk. First was in a old lexus sc300. Surprisingly the SC300 had zero rattle. I can only think it's because the car itself was like a tank. I called the shop and told them to test the system before putting the trunk back together. Right now the box is being dried and the wires are already laid out. I'm hoping for it to be done tomorrow but don't want to rush them. I'll be stopping by sometime tomorrow so they can test the sound and decide if everything is fine. I'm not going to be blasting my music very much. It's mainly just for myself.
On a side note how do you like the cleansweep?
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Joined: Mar 2011
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From: NNJ
'11 C350 '13 F150 lariat
lolo @ pepboys system hahaha.
Yea this will be my 2nd custom trunk. First was in a old lexus sc300. Surprisingly the SC300 had zero rattle. I can only think it's because the car itself was like a tank. I called the shop and told them to test the system before putting the trunk back together. Right now the box is being dried and the wires are already laid out. I'm hoping for it to be done tomorrow but don't want to rush them. I'll be stopping by sometime tomorrow so they can test the sound and decide if everything is fine. I'm not going to be blasting my music very much. It's mainly just for myself.
On a side note how do you like the cleansweep?
Yea this will be my 2nd custom trunk. First was in a old lexus sc300. Surprisingly the SC300 had zero rattle. I can only think it's because the car itself was like a tank. I called the shop and told them to test the system before putting the trunk back together. Right now the box is being dried and the wires are already laid out. I'm hoping for it to be done tomorrow but don't want to rush them. I'll be stopping by sometime tomorrow so they can test the sound and decide if everything is fine. I'm not going to be blasting my music very much. It's mainly just for myself.
On a side note how do you like the cleansweep?
I think the cleansweep is a great product in the right setup. I personally am looking to switch it out, theres not too much out there in its class, Im researching the rockford fostgate 3sixty.3 at the moment, and the only reason being is the volume control issue. JL wants you to mount their knob in the vehicle and use it for control, your supposed to keep your head unit at whatever volume it is when calibrating, and dont touch it. I personally cant live w out steering wheel control of the volume, and Im not about to drill a hole and mount their knob in the vehicle somewhere. The caveat to this is white noise in the background at mute and low volumes, kinda annoying sometimes. I have the cleansweep gain up 3/4 and the JL volume somewhat low like 2/5 volume, and the highpass amp gain low and it took alot away, it was bad before I made adjustments, took some playing to make it livable. The problem is the Headunits have variable EQ settings based on volume, and without the cleansweep's DSP the lower quality MP3s and such sounded like garbage whe I used a regular low pass crossover and then I tried a MTX reQ and that helped a little but the cleansweep did wonders, its the knob that kills it. They shoulda made a wireless one or something other than what they have but for 300ish you get what you pay for. My last C had harmonkardon and sounded perfect, I will NEVER get another benz without it. The MM option isnt enough in the new ones if you dont have HK, I was going custom audio didnt think Id need to pay for speakers/amps I was gonna change out, but the DSP in that system blows anything else away I have heard yet.....
Thread Starter
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Joined: Apr 2008
Posts: 275
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From: San Francisco
C300
Hey Guys,
I got the car back but had a bunch of set backs over the weekend with it. The major problem was 1 of the subs I reused was blown and I wasn't aware. I told them to leave it in for now until I can replace it. The 2nd issue was the lack of free air going to the sub in a fiberglass mold and amp placement. This was solved by leave 2 gaps at the top and bottom of the mold and mounting the amp behind the chair instead of with the box.
Last but not least. With all the adjustments and such the box didn't come out as flush ad I hoped. Its very minor and not noticeable but after he pointed it out I couldn't stop staring LOL. They will fix it though so no worries there. I've ordered 2 new subs JL 12" w3v3 which should be here by Friday so I'll be heading back to the shop to replace the subs and redo the top layer of the mold to sit flush.
Here are some quick shots:
Now you see it:
Now you don't:
New pics to come when I change the subs and they fix the mold.
I got the car back but had a bunch of set backs over the weekend with it. The major problem was 1 of the subs I reused was blown and I wasn't aware. I told them to leave it in for now until I can replace it. The 2nd issue was the lack of free air going to the sub in a fiberglass mold and amp placement. This was solved by leave 2 gaps at the top and bottom of the mold and mounting the amp behind the chair instead of with the box.
Last but not least. With all the adjustments and such the box didn't come out as flush ad I hoped. Its very minor and not noticeable but after he pointed it out I couldn't stop staring LOL. They will fix it though so no worries there. I've ordered 2 new subs JL 12" w3v3 which should be here by Friday so I'll be heading back to the shop to replace the subs and redo the top layer of the mold to sit flush.
Here are some quick shots:
Now you see it:
Now you don't:
New pics to come when I change the subs and they fix the mold.
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Joined: Dec 2010
Posts: 1,170
Likes: 1
From: 626
E63 Black on Black
Hey Guys,
I got the car back but had a bunch of set backs over the weekend with it. The major problem was 1 of the subs I reused was blown and I wasn't aware. I told them to leave it in for now until I can replace it. The 2nd issue was the lack of free air going to the sub in a fiberglass mold and amp placement. This was solved by leave 2 gaps at the top and bottom of the mold and mounting the amp behind the chair instead of with the box.
Last but not least. With all the adjustments and such the box didn't come out as flush ad I hoped. Its very minor and not noticeable but after he pointed it out I couldn't stop staring LOL. They will fix it though so no worries there. I've ordered 2 new subs JL 12" w3v3 which should be here by Friday so I'll be heading back to the shop to replace the subs and redo the top layer of the mold to sit flush.
Here are some quick shots:
Now you see it:
Now you don't:
New pics to come when I change the subs and they fix the mold.
I got the car back but had a bunch of set backs over the weekend with it. The major problem was 1 of the subs I reused was blown and I wasn't aware. I told them to leave it in for now until I can replace it. The 2nd issue was the lack of free air going to the sub in a fiberglass mold and amp placement. This was solved by leave 2 gaps at the top and bottom of the mold and mounting the amp behind the chair instead of with the box.
Last but not least. With all the adjustments and such the box didn't come out as flush ad I hoped. Its very minor and not noticeable but after he pointed it out I couldn't stop staring LOL. They will fix it though so no worries there. I've ordered 2 new subs JL 12" w3v3 which should be here by Friday so I'll be heading back to the shop to replace the subs and redo the top layer of the mold to sit flush.
Here are some quick shots:
Now you see it:
Now you don't:
New pics to come when I change the subs and they fix the mold.
MBWorld Fanatic!
Joined: Mar 2009
Posts: 1,177
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From: UCF area Orlando/West Palm Beach FL.
c350coupe, Gencoupe R-spec
very clean set up sir . Im tempted to do a setup kinda like this, but i wanna do component speakers as well as subs and i dont know if I would need to do a clean sweep as well, and a JL clean sweep alone is $400.. hmmmm lol i miss my Bass
. Im tempted to do a setup kinda like this, but i wanna do component speakers as well as subs and i dont know if I would need to do a clean sweep as well, and a JL clean sweep alone is $400.. hmmmm lol i miss my Bass
Thread Starter
Senior Member
Joined: Apr 2008
Posts: 275
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From: San Francisco
C300
Thank you.
Honestly I don't see a need to change speakers at all if you have the HK system. Though I have 1 dead sub the system still slaps hard and it doesn't drown out the mids/highs from the HK speakers. But! I'm no sound scientist. The clean sweep I wanna try but I can't justify the price if the difference is minimal.
Forgot to mention. They Dynomatted 1 area for me which had a small rattle. It was the area where the trunk liner was (Top of the trunk) I'm assuming cause the subs were facing up? Thanks for the suggestion Jimmy as I told them where to look according to your suggestion.
Honestly I don't see a need to change speakers at all if you have the HK system. Though I have 1 dead sub the system still slaps hard and it doesn't drown out the mids/highs from the HK speakers. But! I'm no sound scientist. The clean sweep I wanna try but I can't justify the price if the difference is minimal.
Forgot to mention. They Dynomatted 1 area for me which had a small rattle. It was the area where the trunk liner was (Top of the trunk) I'm assuming cause the subs were facing up? Thanks for the suggestion Jimmy as I told them where to look according to your suggestion.
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Joined: Mar 2011
Posts: 955
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From: NNJ
'11 C350 '13 F150 lariat
no problem, the trunk top drove me nuts. Those vent flaps will start to make noise too so keep an ear out. If anyone here has a HK system you DONT need the cleansweep, it would be a downgrade the HK DSP processor kills the cleansweep, trust me I have one of each. And if anyone wants one I have a shop near me selling them for 250 cash closeouts. I may sell mine too and go for a 3sixty.3 or the other JL DSP thats like 800, I want something that doesnt have an audio knob required.
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Joined: Mar 2009
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From: UCF area Orlando/West Palm Beach FL.
c350coupe, Gencoupe R-spec
i agree the HK speakers are great and if one of them wasnt already blown id leave them be, but since it is why not switch it up. I might do a single 12w7 or rockford 12" in time, wanna get some other mods out the way first but again nice looking system
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Senior Member
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Posts: 275
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From: San Francisco
C300
I was gonna switch up the subs but decided to stick to all JL. Plus I heard the w3v3's live in their showroom and was impressed. They changed it to a single coil instead of dual coils like the older v2's. Less option but much cleaner, crisp sound.
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Joined: Aug 2011
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2008 c350 Sport
Suggestions?
Looking to find a trustworthy car audio shop in San Francisco to wire tap off my factory HK sub and install my JL setup. Any suggestion? (Tehc300 saw you're from SF so thought I would start here. 
Also, can anyone confirm for me that installing an aftermarket headunit forces the owner to install a new amp to power all the rest of the HK system because they are fiber-optic? I heard there might be some way to work around this issue and keep the factory amp in place with after market headunit.
Thanks All!
(New Benz Owner.)
2008 c350 Sport. HK system.
Also, can anyone confirm for me that installing an aftermarket headunit forces the owner to install a new amp to power all the rest of the HK system because they are fiber-optic? I heard there might be some way to work around this issue and keep the factory amp in place with after market headunit.
Thanks All!
(New Benz Owner.)
2008 c350 Sport. HK system.
