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Audio system build

115K views 351 replies 22 participants last post by  WaltsCLA 
#1 · (Edited)
Ive been planning to a car audio build ever since I bought my CLA. So far my plan is to use the factory radio. Most of the parts are from my prior vehicle.
Equipment:
Alpine H800+C800
Alpine PDX-V9
Scan Speak Revelator 18w mids
Scan Speak D3004 tweeters
Fountek FR89EX center speaker
Alpine Type R flat subwoofer
Random small amp for center speaker.

At the moment, all of the wiring has been has been completed and this car was possibly the easiest car to run wire though. The factory wire guides on either side of the of the car easily accepts 0AWG wire and just about anything else. The factory rubber firewall grommet makes wiring though the firewall a breeze

I am going to do minimal sound dampening because the car is quiet enough as it is. But we'll see. Im going to reserve most of the dampening for the front doors.

This build might take a while as the car is my daily driver and I have to reasonably get it back to stock for the work week.

Main battery fuse.


Factory grommet. The picture is obviously before I poked the 0awg wire through and little wire is for my radar system. The weird thing is, I wanted to buy a backup grommet but the dealer couldn't look up the part number, I also had no success looking that PN online :/


My original plan was to mount the processor and amp under the rear deck. But after removing the factory sub module and speaker Im considering mounting them on top of the rear deck.








Mocked up



I'll add more pictures from time to time when I work on car....
 
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#2 ·
Notice that the pre-collision brain is mounted on the rear deck. I don't have this option so I guess all of our cars come prewired. One of the connector connects to a dummy sensor lol

I would love to re-locate it because It might interfere with the amp and processor but afraid it mess something up.
 
#4 ·
I was able to securely mount the amp + processor and compete the wiring on the rear deck...





There is a conveniently placed hallow rail with holes large enough so I can pass the power, ground and remote wires though, which are protected with added rubber grommets. The fuse block will be directly underneath the rail.





Rear deck goes back on and no one will every know theres anything aftermarket underneath





I will complete the fuse block install and add small amp for the center speaker next week.

So far, I'm happy to say that at this point I have yet to modify anything and everything can be put back to stock.
 
#9 ·
Man that going to be nice! Props on the work! keep them pics coming cant wait to see the finished product!
 
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#11 · (Edited)
I had some family and friends over this weekend, so I didn't get too much done...

Bracket for center channel amp. The board is made of 1/2 plywood & MDF and the brackets are made of 1.5" x 0.125" steel strips


Tight fit but works perfectly. Again, I am using up space that would normally not be used. Both brackets utilize factory bolts or holes


With the trunk liner re-installed. I still have space for the manual and my little tool bag that I usually keep there.



Power wires entering the channel that eventually goes to the fuse and ground blocks. Again, protected with a rubber grommet


Fuse/ground blocks. I will eventually make a panel to cover these.



This is my first major modification - the ground
Factory adhesive and paint removed.


Rivet nut



Modified terminal


Finished ground.




At this point most of the basic work has been completed. Only custom work from now on.
A-pillar tweeters then door mounted woofers are next in that order and finally the sub.
 
#12 ·
I had some family and friends over this weekend, so I didn't get too much done...

Bracket for center channel amp.

At this point most of the basic work has been completed. Only custom work from now on.
A-pillar tweeters then door mounted woofers are next in that order and finally the sub.
Good work, one question and one suggestion...

What kind of tuning are you going to do, I see your DSP has power for both of best worlds, Movie Theater 5.1 and Front stage, what is your goal, watch movies or pure SQ in music in stereo? I could guess your doing a 5.1 because you are going after the Center Channel option.

Suggestion... if you pick the sail panels for tweeters instead of the A-pillars, you will obtain a wider stage and less reflexions from the windshield that tend to skew your image. But everything is relative to your x-over points and slopes between tweeter and mid/bass.


D.
 
#14 ·
Ok, so you are doing a Front stage 1 or 2 seats? from what I read above 1 seat, right?

I have the P99 in my CLA, it's a good DSP the only downside is you can't hide it!

Yes you have more freedom with tweeters in a-pillars but physical locations reduces stage width, that's a fact just measure the distance between a-pillars and compare with sail panels.

What really matters is the direct signal from left tweeter to your left ear, the further to the left the wider your stage, also depends on your x-over settings, and since you are doing a 2 way probably you will be crossing them pretty low covering most of the Interaural Intensity Difference (IID) - where localization determined based on the intensity of a sound arriving at each ear also known as Interaural Level Difference (ILD), anyway it's up to you and you can experiment, everybody hears different and what I like you may not, I'm cool with that.

Any reflection will affect center image that is why a car is the worst place for a high end sound system. The tweeter Mercedes install in the sail panel is very clever and efficient and it's almost direccional avoiding glass reflections. I would use them before trying something else, you may like them.

D.
 
#15 ·
Didn't get a whole lot done this weekend but I quickly cut a couple of rings for the speakers.
Everything was cut with a router, a circle jig and a router table.

The beginnings of the tweeter mounts.






5/8" roundover


These rings will be fiberglassed into the a-pillars


I have yet to remove the factory door speakers and have no idea what the allowable depth is, so I made a pair 3/4" spacer baffles for the woofers. IIRC, when I applied some sound deadening to the door skins the factory speaker has an integrated spacer thats about an 1". I'll add more rings if needed.




Center speaker plate. I wanted something thicker but there really isn't much space underneath the grill. I'll probably fiberglass it to stiffen the baffle.



Chamfered rear baffle to increase air flow





A-pillars next week. ;)
 
#18 ·
Yeah me too, keep up the good work.

I'm interested in your DSP software and how interacts with users,

I like the Bit 10D software but I don't like the fact that I need a computer for tuning. I'm hoping yours will be more friendly user.




D.
 
#19 ·
Electronic device Technology Text Electronics Audio equipment


I've only had time to browse through the screens on the computer. Looks like the Audsion's UI is simpler. Alpine uses multiple windows. Although it might make it faster to assess TA, EQ or Xovers because you can have all 3 or so screens open at one time, it can get confusing. I guess I'll have to spend more time with it.
I hope the C800 is as easy to use as the old C700/701.
 
#21 ·
I was checking out the factory center channel grill last night and there is an issue...

Spare grill


The mid will not be mounted to grill, Its for demonstration purposes only


Straight on. Would be fine if this is facing the driver but it's not, it's facing the windshield.


The cone is now invisable once its at the normal angle to the driver



I came to the conclusion that the factory grill is substantially blocking sound. I am still debating if I need to open up the grill or not because ultimately it's just an ambience speaker. If I change my mind, I'll probably cut it open and add my own fine mesh grill material.
Luckily I bought this spare grill.
This also leads me to question the factory door grills o_O
 
#22 ·
You have all the power you need, from your DSP; you could recreate a sound stage with an awesome center image without a center channel, and I'm afraid you will get a rainbow effect if you use the center channel with the driver facing the windshield having all sort of reflections.

Phasing, Levels, x-over points, slopes, time alignment and Left+Right EQ are your best tools you ever have.


D.
 
#24 ·
On a OEM system, yes the music is playing from all corners from the car, but...

What we hear is the sound coming from the closest speaker to our ears, if you lean to the right or back you will hear the other speakers. Only if you set your self right between 2 sets of speakers a phantom effect will appear somewhere above and or in front (depending on your position between the speakers), this is what we call Center Image. It's like when you listen to headphones... this center image appears to be right in the middle of our heads.


D.
 
#27 · (Edited)
I have a bit of a hangover today so very little was completed.
The center speaker was installed but wasn't able to use the baffle.

Factory vs Fountek. I find it bizarre that the center and the factory sub is a DVC. If they needed a lower impedance load why don't they just use a lower impedance driver?



2 sets of speaker wires going to the OEM speaker. Note the round peg holes to secure the OEM speaker was plugged with rubber grommets


Mid installed. I couldn't use the baffle because I forgot to account for the lip about the driver, the driver flange and MDF are too thick. So I simply put down a layer of closed cell foam (Rammat Ensolite, I think) and screw the driver down. Worked perfectly. I also added foam around the voids and open areas to avoid sound wave cancellation



Factory grill snapped back on.


I will start and hopefully complete the A-pillars this weekend.
K, back to sleep.....
 
#28 ·
I am starting on the doors early because there is an awesome deal on a great set of speakers right now and I want to know if I can get my woofers to fit. If not I'll buy the new speakers.

First, there are several good DIY threads on this forum that really helped me remove my doors without damaging the doors.
Second, some hacking was involved when I removed the factory speaker. :D

Door removal.


The plastic/metal strip needs to be removed to access the screws.


The plastic trim remover was very useful here. I started on the end closest to the front of the car and moved back. You have to pop the clips from front to back before completely removing the trim.



The trim



There are two T30 tor screws that needs to be removed.




The door is now ready to pop open. One thing to note, the door goes straight out, there isn't a lip where you have to pull the panel up for removal. Because of that the tweeter housing doesn't have to be removed.



When you get to the upper outside edge note this little tab. It needs to be pulled out to fully release the door card.


I used a pick tool to pry it out



Once the door card is separated from the door there 2 plugs and the door handle that needs to be removed.
Maroon and blue plugs




And the door handle hook


Pull back the blue sleeve on the right and you should be able to remove the wire out of the slot.


Release the hook
 
#29 · (Edited)
Inner door skin. Note that I already did some sound deadening in the past.


Quick measurements of the speaker

Spacer depth


The entire inner door panel is a plate made of plastic that is riveted in place.


Because the speaker is riveted from the back, at this point I can either remove every rivet or simply cut the speaker surround to access the rivets.
I chose the latter.


3 rivets hold the speaker in place


After drilling all 3 out the speaker now can be pulled out


A quick comparison of the speakers


The total height of the OEM speaker is 34mm


The new speaker and 3/4" spacer is about 27mm. So this gives me room for an additional 1/4" ring


Depth measurements
To the glass

To the plastic window retainer


This in addition to the 1" spacer gives about 3 1/4 depth. More then enough room for the 3" deep speaker.
The main issue is the overall width of the factory speaker. It is barely 6.5" overall and the surface behind the speaker tapers off significantly.

The new speaker is obviously way too large for the factory opening


I copied the OEM speaker mounting technique. The 1/4" spacer behind the 3/4" spacer is slightly smaller so it can be secured to the door.


Temp mounting using double sided tape.


One thing that kind of bugged me. The plastic is pretty cheap. I thought it was made of fiberglass or nylon plastic. Nope, maybe a composite but still very flimsy to say the least. I thought I needed a jigsaw or a Dremel. All I had to do was use the ring as a template and kept scraping the plastic with a sharp pick.


The centering of the hole with the door attached. Not bad


And it fits!

Speaker with the door reinstalled


Not that I know the speaker fits, I applied a layer of fiberglass resin to water proof the rings. I also added more deadening to the flimsy plastic.

More pics tomorrow, I decided to take the rest of the day off to watch football :D

One thing I found was they styrofoam on the bottom of the door. It is about a foot long. Not sure what it is but its loose, I was able to pull it up several inches.
 
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