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Upgraded my sound system!!!

32K views 27 replies 7 participants last post by  Underpressure99 
#1 ·
Alright, having fixed all the mechanical / electrical issues with my car, and having begun to do some cool retrofits, I thought it was a good time to upgrade the crappy factory sound system (non-bose). Liking the practicality of my car and the factory look and feel of my car, I wanted this to be an epic upgrade, without sacrificing the coolness or function. By that I mean, I did not want to have speakers too big to fit in the door, causing the windows not to be able to roll down all the way, or to have an enormous subwoofer box in the trunk, or to get an uncle ben's bistro express rice cooking aftermarket headunit. I love the look of the becker head unit (and that it works with my factory 6CD changer in the trunk), and as my sound system currently is, the head unit does not need to be replaced in order to have an epic sound system, which is good news for those looking for an upgrade but keeping the headunit.

The Parts:

CT25MC03
CT25MC04
CT25MC10

Those are the speaker pods, for front doors, rear doors and hat shelf respectively. Punch those into ebay, they are part numbers, and you can buy them, they are very cheap, and much easier to use those than trying to remove the factory speakers from the factory pods.

Polk Audio DB501 - rear doors
Polk Audio DB651s - front doors
Polk Audio DB1001 - tweeters
Earthquake Sound SWS-6.5x - Hat shelf
Kicker CX300.1 - subwoofer amplifier
Kicker CK8 - wiring kit
Rockford Fosgate Speaker Line To Female RCA Adapter
StreetWires FSAFS40 Fuse-AFS-40 Amp

Now, if you are waiting to do a similar procedure, it takes about 4 hours for the doors, 2 hours for the tweeters, and 6 hours for the subs + amp. So break this job up into parts so you don't go nuts.

Front doors - pain in the #$^@

The pain with installing the front door speakers was the the speakers don't fit in the speaker adapter, the speakers are too small. To make them work, I grabbed a hacksaw, and sawed into the metal rim around the speaker, opening up 4 tabs that I then drilled a hole through to pass the screw, doing that made the speaker fit. Then I used the included gasket, as well as some hot glue to make sure the speaker is sealed well around the adapter, you don't want air to be whizzing through there. I also used the included foam to seal up some funny volumes around the perimeter of the adapter. I also tried to put a foam strip around the speaker, to improve mid-bass, but the cover would simply not get back on. Turns out you really don't need it anyway. Putting the adapter with speaker into the front doors is easy, and you don't need to cut out the baffle, the speaker fits as it is a slim-mount. I just soldered on the factory connector to the speaker, making removal if needed very easy.



Rear Doors - Also pain in the @$#^

I begun by simplying my life. I used a propane torch heated exacto knife to cut away the excess plastic preventing you to reach 2 of the 4 screws. Use your head here, cut out as little plastic as possible, and keep in mind it will all be covered up by the cover later anyway, so don't worry about it looking bad. Make sure you are in a well ventilated area, melted plastic smells terrible! This time the speakers were a perfect fit into the adapter. I just used some hot glue to seal up the gaps between speaker and adapter, then soldered on the factory connector, pop into the door and it's done! I also put the included foam strip around the speaker, this time, the cover will go back on no problem.

You can actually see in the picture below, I melted off a bit too much plastic to the top right of the speaker, but it's ok, it's still covered by the cover, just be careful! (Luckily on the other door this didn't happen)



As it is now, you will notice a huge improvment in the quality of the sound, these speakers are very good, and very sensitive too! 91dB front and 93dB rear, so you will need to use much less volume coming from the headunit for the same level of sound as compared to the factory paper speaker. The tweeters in these speakers make the highs sound much clearer.

Tweeters - still a pain in the @$%#^

Now, an often overlooked part of a sound system upgrade are the tweeters. Tweeters will really tie everything together, and make the sound feel in your face! Begin by popping off the grills on top of the vent. Sadly, the Polk's do not fit under the grills in their factory shroud. So ou have to delete the shroud. Do so by exacto knifing the adhesive on the back, and gently pry off the plastic tabs. Eventually you will have all the plastic tabs off, and the metal grill off too. Be extremely careful and gentle, as exposing the tweeter means you are exposing the very sensitive textile dome. Now, the factory tweeters are crap, and you can't even hear them they are so weak, just pull them out of the grill, they are held on by tabs. Then with your friend the heated exacto knife, you will have to melt off most of that holder. Keep in mind, you need to leave it enough depth so the tip of the dome does not touch the grill. Mine ended up touching just a tiny bit, I left it there. The best way to hold the tweeter to the grill is with hot glue, get nice and all around. Be sure that you file away any sharp edge of plastic that was left by knifing through. Also, you will have to file the inside diameter of the hole, to make sure it lines up with the part of the tweeter that isn't hard. You will also have to kep in mind the alignement, the tweeters are much bigger than the factory ones, so just first give it a test run with a pit of glue and make sure they fit back into the hole.

Now you will also have to solder on the included high pass filter. The yellow wire is the +3dB boost, cut it to have no boost (I cut mine, and istead adjusted the tweeters with the radio, just giving it +1 notch of treble really brings out the 6 total tweeters). Again, I used the factory connector, to make removal easy. I just tucked it all into the dash when I was done, the filter won't move around much in there.




Once it's all tucked away, no one's the wiser!


Apparently something's living rent-free and enjoying the included salad package in the garage...


At this point, once the speakers have had the chance to break in, you will be like wow! this sounds amazing! But you will also find the lack of bass disturbing... I'll write a reply to cover the sub-woofer installation in a few hours, need to get a few things done now!
 
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#2 ·
Hat shelf subwoofers - this part is genuinly fun

Alright. First things first, you do not need to remove the hat shelf, or the seats, or the headrests, or anything. Just pull off the covers, and take out the first aid box, and that's all you need to access those speakers! I decided to remove my useless car phone speaker, and replace it with a block of foam I bought from the dealer, it costs 23$ special order item so it takes 10 business days to recieve. Now, remove the old speakers by popping out the 2 tabs from the inside the trunk. And get use to being in the trunk, you will spend a few hours there. Note that the rear door speakers are bridged at the connector for the hat shelf speakers. Again, I kept that connector, but this time it will obviously not g directly to the subs. Instead, you have to solder the speaker wire to RCA adapter to the plugs, and mind you have to do it from both sides! I used the rockford fosgate line to RCA because it's the only one I found which clearly differentiates left/right and +/- . Once you have that soldered and taped on, get a short RCA wire, you won't need much of it. I popped the RCA leads out of a hole in the center of the trunk, somewhere underneath the rear tailight. Next it's time to get the amplifier wiring done. Pre-facelift models you will be lucky, just splice into the +12v signal from radio to power antenna for the amplifier remote start, run the ground cable to the left rear wheelarch ground point, and power goes to the battery on the right. Use zip-ties liberally to get everything to look clean. No need for crimp on any connectors on the amplifier side, just strip a bit of wire and stick it into the amp and screw it in. Speaking of the amp, I used 3/4 inch long self-drilling machine screws, and a thick nut to space the amp out (the medical box has a small plastic lip that sticks into the trunk, you need a bit of clearance to get the medical box back in). Once you have the screws in, ou will have to remove them and use bolt cutters to shorten them, otherwise they protrude too much, and the medical box won't fit back in. This only needs to be done on the front most 2 screws, but I did it on all 4. Next is to get the amplifier on there tight, and just wire it, use more zip ties to keep it clean. I found a perfect location for the fuse holder, refer to picture for that, I used 2 zip ties and 4 holes drilled into the lining to keep it there. Just remember to replace the 60 amp fuse with a 40 amp fuse. Solder the speaker wires to the subs, and hook up the other end to the amp. Popping the subs back in is simple enough, once you get it in the hole (will require some force and patience) and you have it lined up, start by pulling the outboard tab in with some pliers, then pull down on it until the inboard tab clicks in. Again, use zip where necessary to keep everything tidy. disconnect the negative from the battery, wire the amplifier to the +12v on the battery, reconnect negative.

Now, you will be dissapointed by the bass in your car, but don't worry, these subs have an enormous break in difference. I've never heard speakers change so much during a break in. They went from sounding totally flat and dull, to (and I'm not exagerating here) like I have a 1500w 12" sub in a sealed enclosure (very deep resonant base). So once they have broken in, adjust the cross-over and gain on the amp to your liking. Gain of 4 is honestly too much to my liking, but 3 is perfect, 5 will blow your windows out, and don't go higher than that, the amp is much stronger than the subs can handle. I've got the cross-over at about 110Hz. Don't use bass boost, it is really not necessary, and might add distortion if you use too much.

You will notice a lot of things shaking on your hat shelf that did not shake before. Here is how you can remove all the shaking and vibrating. First, duct tape down all the wires. Then, I bought 4 large sponges at my local hardware store. I stuffed 1.5 sponge behind each sub, under the hat shelf towards the back (where it meets the rear window). I also cut a small section of sponge, and stuffed it between the center metal support for the hat shelf, and the actual hat shelf, this is where the vibration was at its worse for me. you need just a thin slice, too thick and it will make a bulge on the hat shelf, and your first aid box won't close right. This totally solved all the vibrations for me. Feel free to add more sponges, this works surprinsingly beautifully, and is way cheaper than professional insulating material.

But how is the bass? Honestly, 10/10 does bang. In the front seats, it is very deep and resonant and punchy as a result of constructive interference. In the back seats, it's quieter, so it won't bother any passengers, but there is still enough of it in the rear to keep it interesting.

The way all the sound meets up in the front of the cabin makes for an absolutely stunning sound system. I'll be honest, this is better than any factory system, upgraded factory system or after market system I've ever heard. Sure you could drop way more money and get a slight improvement. But for ballpark 800$ CAD, this will blow you away. The Becker 1692, coupled to right components, is just a fantastic radio.

Pictures!!! (no particular order)








dat focus though


 
#4 ·
Hey! Got a really nice setup there. I am really curious, how's the Earthquake Sound SWS-6.5x sound? How much bass those produce, it is really worth to buy those. Searching for myself something to exchange the old hat shelf speakers to a newer ones. Actually would be really cool, if you'd post some video "audio system test". Thanks in advance.
 
#5 ·
Thanks! The Earthquake Sounds are amazing! With the amplifier, you can easily have massive bass. I would recommend those to anyone looking for upgrading the factory subs. I can try to film an audio test when I have a bit of time, but I don't know if my DSLR's built-in microphone can do it justice.

On another note, I discovered that you can use the same speaker adapters for the 2 inner holes on the hat shelf. What I might do soon is add a second, full range amplifier in the trunk (I'll move my subwoofer amp a little bit to the left side), and run an extra pair of coaxial speakers on the hat shelf (firing into the cabin instead of the trunk). This really isn't necessary, but I might just go over the top with it for the heck of it!

But I can definetly say, as the entire upgrade is now, it's just perfect no matter where you set the volume. With the amplifier, bass can be adjusted from balanced all the way to insane!
 
#6 · (Edited)
Alright, I did a few minor changes, and I will do another few minor ones next week. I redid the tweeters, spaced them out a little bit more so they don't touch the covers and I glued them back in more solidly. They do sound a little bit clearer, and idk if I mentionned it already, but I soldered back the yellow wire on the high-pass filter. That got me my +3dB back. Turns out the dash does attenuate them quite a lot, and they aren't pointed directly at you, so leaving the yellow wire alone is a better bet.

Now, what I am planning to do is to drill 4 holes into each subwoofer adapter, and screw them into place. Also, I will put more foam under the hatshelf, to keep anything from rattling. I will use the same thing I did before, which is to buy large sponges and cut them into shape to fit them in nice and snug. That already reduced most of the rattles, just need a bit more foam (the subwoofers are actually pretty powerful). I'll also post a picture of my amplifier's settings, I found the sweetspot, and it sounds at its best there.

On a side note, I replaced the plastic trim in the rear doors with wood, looks much better!







 
#7 ·
Looking great! I have only upgraded the front doorspeakers. I just cut the factory adapter out and soldered the wires directly onto the new speakers, how did you install it exactly with the adapters still in place?

Also what size are the hatshelf subs? Im looking into upgrading mine. Thanks in advance!
 
#8 · (Edited)
Well all the adapters are removable, so I just removed the factory ones and replaced them with aftermarket ones. While I had the aftermarket adapters out, I installed the speakers into them, so putting them back into the car was plug and play.

Hat shelf subs are 6.5 inches, same size as the front door speakers. I would recommend the earthquake sounds, they sound great and they fit perfectly. You will need an amplifier to drive them though.

Since you have the facelifted model, you don't have the automatic antenna in the trunk. So getting a +12v signal to start the amplifier might be a little bit more involved. I'm thinking you could sacrifice the car phone speaker, and use one of its wires to carry the 12v signal to the trunk from the radio. Even though you don't have the antenna, your radio should still have the +12v on signal for activating the antenna. That is, if you still have the factory radio.
 
#9 ·
And, of course, I could never attempt this as the Polk speakers are not available in my country... we keep missing out on the good stuff...
 
#10 · (Edited)
-97 still no facelift here :) I found these very nice sets with carbon cones, theyre the best bang for buck set in Finland.

http://www.biltema.fi/fi/Autoilu---...paketti-2-tiekoaksiaalikaiuttimet-2000030783/

Im still quite baffled how you got the signal wires done? You put RCA on both left and right original shelf speaker wire and then your amp had the input for left and right speaker signal? Then you connected your new speakers to the output of the amp right? Its now true left and right setup, you can adjust them from the headunit?
 
#13 · (Edited)
Im still quite baffled how you got the signal wires done? You put RCA on both left and right original shelf speaker wire and then your amp had the input for left and right speaker signal? Then you connected your new speakers to the output of the amp right? Its now true left and right setup, you can adjust them from the headunit?
Sorry, I missed that part of your question. You're right though, I didn't fully explain how I got those RCA connections done.

I bought a speaker wire to RCA adapter, and I just soldered that adapter in place of the old plugs for the factory subs. The signal there is amplified by the radio's amplifier, so it's a speaker level signal, not a line level signal. The kicker amplifier has a switch for selecting between line/speaker level inputs (it's the HI/LO button). And yes, that does mean I can still adjust the left/right balance, but keep in mind this is a mono amplifier. actually, it combines the signals from the left/right channels in order to make a stronger, mono bass signal. If I inplug one of the RCA cables, I still get bass, but about half the loudness. However, if I were to add a full range 2-channel amplifier, then the same trick would work.

I do actually want to add a full range amplifier in the rear eventually, to amplify the rear door speakers and another set of coaxial speakers that I'll add in the vacant spots in the hat shelf. I've raised the crossover frequency on the subs' amp to 100Hz (I was at about 90Hz before), in the eventuality that I add amplifiers for the front and rear speakers. Given my setup, 100Hz on the aubs and 120Hz on the coaxial speakers would be a good place to start.

I should borrow from someone a high-quality microphone that I could use to record the sound inside my car. A lot of people say a 6.5" sub is not enough, but I beg to differ. My current setup goes pretty low, and does not have any localization. Bass feels like it's coming from all directions, you definetly don't feel it coming from the rear of the car, the audio techs at Mercedes were definetly on to something by firing the subs into the trunk, but their efforts were thwarted by terrible factory speakers.
 
#12 ·
Well mine can do 50-40 Hz, it's not as loud obviously, but the bassboost on the amplifier lines up well with the EarthQuake Sound's resonant frequency. The bass boost is 40 Hz and the frequency is 39 Hz, so giving it about +3dB bassboost made them a bit more punchy. Also, keep in mind they fire into the trunk, and the large volume of the trunk amplifies lower frequencies. There is actually a big drop in bass as soon as the trunk is opened.

But in any case, I'm not a huge fan of excessive bass, so it worked out well for me.
 
#14 ·
Update time!

So I decided to tackle some of the remaining rattles caused by my strong subwoofers sitting on the hat shelf. I did 2 things: First I bolted the adapters to the metal under the hat shelf with some self-tapping screws. I only managed to put 2 screws per adapter, since there were only 2 accessible corners on the adapters. This part was slightly ghetto-rigged, I used the screws to drill through the plastic, and then I pushed and turned hard on them with my ratchet trying to create a dent in the metal underneath, which I could then see from the trunk and use a drill to make a hole. Then I just screwed them down nice and tight and used some bolt cutters to cut off some of the excess screw sticking out into the trunk. You will want to use 1 1/4" length screws here, since there is a gap between the adapter and the metal. You also don't want to screw them too tight, because then you'll be distorting the adapter, which may lead to some other problems.

The next step was to add foam! Buy some large sponges from your local hardware store and some long, sharp scissors to cut the sponges. I stuffed the sponges all the way underneath where the rear windshield meets the hat shelf, a thin slice between the center support of the hat shelf, around the first-aid box, and thin slices to squeeze between the covers (they actually rattle the most!). I am quite pleased with how it turned out! No more rattles either :)

Also, replaced the door lock bushings with chrome, looks nice! (But I will not be adding any other chrome to this car, the door handle and the door lock pin bushings is plenty enough!).

On a side note, anyone have an explanation why I suddenly have bad radio reception? I get a sort of buzzing noise on all stations, and I have not changed or messed with anything that could cause that. CDs and tape-to-mp3 adapter still sound crystal clear.





 
#18 · (Edited)
Stumbled upon a "warehouse spring cleaning" sale at a local audio shop and pretty much bought all I need from there. The sales were from 50% to 60% so I just could not pass up.

Bought a 12" cased quality sub for 95€. Thats the recommended price of the sub element itself, so a huge deal there. Its rather large, but Its easy to pop out if I need all the boot space since I have an external amp.

The sub is 350W RMS at 4 OHM, and the amp is 320W at 4 OHM. Also picked up a pair of coaxials for 20€ to replace my rear door ones with. They are 69€ online so again a huge deal. Amp also recommended price 99€ online, got it for 40€ from the sale.

I went with 12" because I want to hear the 30-40 HZ wavelenghts that I have been missing for years, the 6,5" just physically cannot produce those frequencies adequately. I am also going to keep the gain low so Its not going to be loud to the outsiders, and I know I can find 100 new rattles if I crank this setup on high volume.

I am also going to run RCA cables along with remote to the headunit and heard theres factory cable routing going on the battery side along the doorsills.

I wonder what is under the carpeting of the rear seats from the trunks side? Is it metal or plastic or wood? I guess its metal. Anywho I am going to bolt the amp to that area most likely.
 
#19 ·
It's definetly going to be metal under the carpet, so some self-tapping screws will work fine. Usually amplifiers come with some mounting hardware already.

If you want to use the remote bass from the headunit, you could use the wiring for the car phone. I didn't have the car phone option, but the car phone speaker and wiring harness were there anyway, so you might not have to tear anything out to run some wires, just use what's already there!
 
#20 ·
Its rather simple, the plastics need to be lifted off from the sill, not a big or hard thing to do.

But I had a little fuckup already, I bought 6,5" coaxials rather than 5" to the back doors. Maybe Ill leave the rear doors alone and put the coaxials in the parcel shelf.

Or how did it seem, is there adequate space for about 2 inch deep 6,5" coaxials in the rear doors? I can order a 6,5" MDF spacer if there is a flat surface it mounts into? I can cut the plastics no problem, they get hidden anyways.
 
#23 ·
Yeah you can reuse the stock adapters. But I figured the aftermarket ones are so cheap you might aswell save yourself the trouble. The aftermarket ones are a much tighter fit on the hat shelf than the stock ones, as for the door adapters, they will give you a little bit more clearance, as they push the speaker out a little more.
 
#24 ·
mini update time. After I realized I had reversed the polarity on my tweeters, I had to rewire them, which of course meant cutting the factory connectors off because I did not have the foresight to leave enough wire to do a second rewiring job. With too little wire left, I soldered the tweeters directly to the factory wiring. After some time I realized that would be a bad idea, so I cut the tweeters again so I could crimp + solder on some butt connectors. After some time, I realized that was too much of a ghetto rigged operation to be acceptable on my car, so I cut the rigged connectors off and soldered on some proper connectors. I bought some marine-grade waterproof connectors on amazon for 10$ (it was a pack of 5 female and 5 male connectors) and did the job one final time. I also used heat-shrink tubing to insulate the soldering jobs, and used good quality electrical tape to prevent anything from ever coming loose. Here is a picture of the passenger's side tweeter after it was completed!

 
#25 ·
This thing is not that subtle :D I'm once again looking for upgrades, possibly a more responsive subwoofer but most definetely going for the tweeters now. My only concern now is that how do I pry off the tweeter cover without breaking it? What part of the triangle I pry and to which way?

 
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