2018 Civic Hatchback - CDT Audio, Sundown Audio

Hello all! I'm a relative newbie here, but not to car audio in general. What better way to introduce myself to the forums than to start a build log! With that said, it's been about 5 years since I've done anything car audio related. My last car was a 2003 Subaru Impreza Wagon with dual Silver Flutes in the doors and dual full-range's in the dash corners, running a basic active crossover setup off an 80-PRS. On bass duty was a v.1 Sundown X12 in 3.5 cubic feet and tuned at something ridiculously low (29Hz, if I'm remembering correctly). I sold that car in 2016 and have been driving a company vehicle ever since...but, the company just sunset the vehicle program and I finally have a personal vehicle again, which means it's time to start a new build!

Here's the plan:

Vehicle: 2018 Honda Civic Sport Hatchback
Radio: Kenwood DMX957XR (with proprietary Kenwood dashcam)
Front Speakers: CDT ES-062i
Front Amp: Soundstream REF2.370 (the reboot model, not the original)
Rear Speakers: Stock, off deck power
Subwoofer: Sundown X12 v.1
Sub Amp: Hifonics BRZ1700.1
Sound Deadening: Sound Deadener Showdown (CLD tiles, MLV, CCF - stuff I'd bought years ago before he shut down)

Some of these items I've bought new, others I'm pulling out of storage. All power wire, speaker wire, RCA cables and distribution are Knu Konceptz. For the subwoofer enclosure, I'm dusting off a design I'd put together before I sold off the Subaru, which is a horn-ish ported enclosure. I never got around to building this enclosure, but the math was all done and the layout was built in Sketchup. I've since lost the math/details, so I don't have any of the specifics, but I more or less knew what I was doing back then (these days, probably not so much). If that ends up sounding terrible, I still have the Sketchup file for the old box, as well, which I know works well.

I'm down to the last few minor items I need to buy for the install, mostly aesthetic at this point. I've taken the week of September 6th off to do the build and the install, so once I get going, I'll start dumping pics.

More to come soon!

Keep this in mind. Your fronts will have the capability of 110 watts per side from the amp and your rears will have about 8-15 watts from deck power. Be sure you plan or wire it so the rears can be turned down/off because they will run out of juice long before the fronts get tired. Low level listening shouldn't be a noticeable issue. You start to turn it up and the rear will fall apart.

I am looking forward to what you put together.

oh, of course! I didn't note that I'd be fading all the way forward (or turning the rear channels off entirely, if the Kenwood has that function) - the rears will only be powered up when I have rear passengers, which will be rare.

Finally taking a moment to do a brief write up of the build -

Starting with the car: 2018 Honda Civic Sport Hatchback, with a manual transmission. I bought this about two months ago and have been buying up everything I've needed since then.

Attachment 16321
https://www.caraudiojunkies.com/cdn-...pg-jpg.311275/



Now, the enclosure. This is something I'd whipped up for my Sundown X12 several years back. At one point, I was exploring transmission lines, horns, etc. and was doing some modeling in Hornresp. I've since forgotten a majority of the specifics (and how to use Hornresp), but I still had the Sketchup file from when I had first mocked it up, so figured "why not?" and dove face-first into the experiment. It's largely based off of another design I'd found on a forum long ago that was modeled by subwoofer guru Hexibase, and reverse engineered from there. I couldn't tell you any of the specifics anymore, though.


https://www.civicx.com/forum/attachm...72-jpg.311120/



From there, I took some measurements of the trunk and threw together an additional mock-up of the trunk and a possible amp-rack in Sketchup:


https://www.civicx.com/forum/attachm...84-jpg.311123/



I was relatively satisfied with this, so decided to forge ahead from here. Which brings us to last week: I took all of last week off to do the entire thing from start to finish. On Monday, I built most of the enclosure. It was relatively straightforward; I only needed two angle cuts: 7 degrees on the front baffle, and 7 degrees on the baffle edge of the inner port wall. Everything else was a standard cut. A few screw up's, here: one on the outer port wall, where I measured from the wrong side of the blade, which made the board about 3mm too short. Since I'm covering it with beauty panels, I left it as-is. The other was when I mistook a nail hole for a sub-mount mark, and drilled an extra hole (see where the painter's tape is) - filled that with silicone and glassed it over from the inside. That mistake cost me a few hours, but it was correctable.


https://www.civicx.com/forum/attachm...88-jpg.311124/



I used 3/4 inch birch ply for the box, as opposed to mdf, for the weight savings.


https://www.civicx.com/forum/attachm...89-jpg.311126/



Foam tape and tie-downs for the speaker wire


https://www.civicx.com/forum/attachm...90-jpg.311128/



Using SpeakOn connectors as a quick disconnect for the box. Very secure, and very convenient. I've seen some commentary elsewhere that the voltage limits of this connector might pose some issues, so I'll keep an eye on it and change course, if needed. So far, so good.


https://www.civicx.com/forum/attachm...91-jpg.311129/



Test fit into the trunk, along with the beginnings of the amp rack. To cut the amp rack, I took out the trunk carpet, traced it onto the wood, and then cut it out from there.


https://www.civicx.com/forum/attachm...92-jpg.311134/



I was pretty happy with the fitment, so now it's time to put some work into the amp rack. I didn't document the full process, but here are a few final pics. Several hours were spent planning and organizing the wiring, but do it right once and you won't have to do it again, right?


https://www.civicx.com/forum/attachm...93-jpg.311135/



Amp rack includes an extra battery for the system, which is tapped into distribution blocks for both power and ground. The distro blocks have dual 0-gauge inputs, so the battery will feed into one input, while the main power and ground wires will tap into the other input. Wire ferrules and heat shrink on every wire, except for the battery posts, where the holes were too small to accept the ferrule. The distro blocks then go to each amplifier, 0-gauge output to the sub amp, which here in the pic is to the right of the rack, and 4-gauge to the main speaker amp, on the left. That amp then feeds into the passive crossovers for the speakers. I also ran two separate remote turn-on leads, since I plan on wiring the sub amp to a kill switch. Probably unnecessary, but nice to have, just in case.


https://www.civicx.com/forum/attachm...95-jpg.311136/



https://www.civicx.com/forum/attachm...94-jpg.311137/



Test fit into the trunk. It's snug, but it fits! Millimeters of clearance between the amps and the trunk walls. To bolt this down, I used the same mounting locations for the trunk floor and bought some longer bolts at home depot.


https://www.civicx.com/forum/attachm...96-jpg.311138/



One last test fit with the box:


https://www.civicx.com/forum/attachm...97-jpg.311139/



Looks good to me! Now, to hide everything. I wanted to build some beauty panels that highlighted the wood grain, but also provided a window on top to show off, well...whatever I wanted. You'll see what I mean in a moment. First, the front panel.

I didn't document the whole process here, but this is 1/4 inch ply that's been strategically cut to fill in as many open voids as possible. I also stained the front of the box, so it looks just a little nicer. To secure it to the box, I cut little flaps into the carpet - 3 each on both the left and right edges of the box, secured it with some half inch screws, and then folded the flaps over. There are two additional screws right in the middle of the top and bottom edges.


https://www.civicx.com/forum/attachm...00-jpg.311140/



Moving on to the top panel. I also didn't document this process, but it's essentially the same as the front. I wanted a "showpiece" of sorts on the top, and to do that, I decided I was going to swap out wall posters. I got this poster off of RedBubble, and if/when I get bored of it, I'll just buy a new one and swap it out. It effectively allows for an entirely new/refreshed look whenever I want, with hardly any work whatsoever. Securing this panel was the same - 3 screws along either side, and one in the middle of the top and bottom edges.

I'm pretty pleased with how this turned out - what do you think?



https://www.civicx.com/forum/attachm...06-jpg.311141/

Now that the big part is out of the way, it's time to run the wires. Unfortunately, I didn't document ANY of this, but I'll describe the process. I removed the rear seats and the driver's seat, and loosened the bolts in the center console so I could work around it. I pulled up the carpet and ran the bundle of RCA cables, speaker wires, and remote turn-on leads right up the middle, along the left side of the center console. I ran the power wire down the left side of the car, along the door line. Running the power wire into the engine bay was surprisingly easy, and I didn't need to cut any grommets or drill any holes. I've seen people on the CivicX forums run it through the main grommet that exits behind the battery, which seemed like a lot of work that I didn't want to do. I ended up finding a pretty convenient grommet: if you follow the hood release cable into the fender wall, you'll notice that there is an unused hole right above it that's sealed with a grommet plug. This hole is just large enough to feed a 0-gauge wire through - it's not large enough for one of the plastic clip-in grommets, but the basic rubber edge grommets works just fine.

Here you can see where I ran the power wire along the inside of the fender and to the battery. I've yet to complete the big-3, because the alternator is in a very inconvenient location - the back of the engine. I need to rent some lift time to get it handled, I think.



https://www.civicx.com/forum/attachm...14-jpg.311142/



Moving on to the doors and the speakers.

This car still had the stock speakers, which were okay, as far as stock speakers go, but definitely needed upgrading. Just look at the comparison between the stock speakers and their replacements



https://www.civicx.com/forum/attachm...21-jpg.311143/



https://www.civicx.com/forum/attachm...20-jpg.311144/



I could have documented this whole process a bit better - at least I have a few pictures. I started by fishing the speaker wires through to the door. To do this, I straightened out an old wire hanger and, after a few attempts at getting it through, found just the right bend radius that eventually got through both sides. From there, I used a healthy amount of electrical tape to secure the wires to the hanger and carefully pulled it through.


https://www.civicx.com/forum/attachm...16-jpg.311145/



I added some sound deadening to the outer shell of the door, following the Sound Deadener Showdown method of roughly 25% coverage. I added a bit to the inner shell of the door, behind the vapor barrier, as well, but I did not document either of these.

The Sport Hatch did not come with tweeters in the sail panels. To account for this, I simply bought the sail panels from the upgraded trim model from my local Honda dealer. For both left and right, the total for these was all of $25. There's not really a good way to hold the tweeters in place, here, but a couple strips of foam tape seemed to do the trick. If, for some reason, that ends up failing down the road, I'll go back in with a bead of high-temp silicone sealant.


https://www.civicx.com/forum/attachm...73-jpg.311164/



To mount the new speaker, I took the replacement speaker adapter and applied some sound deadening to that, as well, to make it a bit more solid - I filled the voids on the back-side of the adapter with butyl rope, then covered that in foam tape. To get the speaker itself to fit into the door, I needed to take some sheet metal snips to the bits of door near the bottom speaker clips, and then rounded them down with a wood block and a few hammer blows.

Once that was done, I put a CLD tile over the mounting hole, placed the speaker adapter, sealed it off with butyl rope, mounted the speaker, and placed the foam ring. I also have Boom Mat foam baffle sandwiched in here, too, for water protection.


https://www.civicx.com/forum/attachm...22-jpg.311149/



The door panels, themselves, I covered in CLD tiles


https://www.civicx.com/forum/attachm...23-jpg.311150/



Prior to mounting the door panels back on the door, there was one more step that needed to get done. Again, following the Sound Deadener Showdown method, I glued some closed cell foam to a sheet of mass loaded vinyl and mounted that to the door. Here's a before/after


https://www.civicx.com/forum/attachm...24-jpg.311151/



https://www.civicx.com/forum/attachm...25-jpg.311152/



I did not snag a pic yet of the reassembled door, but it all went back together with relatively little issue. The foam rings gave the most problems, but even then, with just a little love, the door panels clipped right back in.

Moving to the cockpit of the car, I added some switches to the panel blanks in the lower dash. From left to right, we have a 3-way toggle switch to retain the factory camera views (which I haven't yet got to work, more on that in a moment), the sub kill switch, which is an led-lit button that lights up red when the amp is on, and is off when the amp is off, and to the right of that, I cut in a voltage display.


https://www.civicx.com/forum/attachm...07-jpg.311153/



And this is where I stop, for now. I've ran into a few issues that still need correction. First, I ordered the wrong dash kit for the radio, so I can't yet get it mounted in the dash. That will be delivered in the next day or two, where I can continue. Next, I haven't been able to get the rear-view cam to work, at all. I'll need to go back through and fiddle with the wiring, but at the moment, it's kaput. The 3-way toggle idea I pulled from a thread over on the CivicX forums, but the thread wasn't as detailed as I'd have liked, and I'm not so sure I got it all correct. It involved some wiring that I'm not exactly comfortable with, so I'll likely need to consult some experts. So more to come, there. I'm also having issues with the steering wheel controls, so I'll need to fix that, as well, but it's low on my priority list.

I did, at least, have the opportunity to plug the radio in, dial in the amplifiers (by ear, at the moment, proper tuning to come, hopefully - I don't have any of the necessary equipment for a proper RTA tune, so I'll likely need to consult an expert here, as well), and play around a bit. I'm very pleased with these CDT speakers. Incredibly detailed, monstrous amounts of midbass, and the doors are bulked up enough where I haven't yet noticed any major buzzes or rattles. The subwoofer, though...by god, I've missed bass. It's great. That's all I can say about it at the moment.

In any case, more to come. Once I get the radio officially in I'll post a few more pics, and once I get everything dialed in, I'll post some more substantial thoughts on the overall build. At the moment, at least, I'm pretty pleased!

I saw this on Reddit the other day. Good work.

Hey, fellow redditor. Yep, I was posting there as I was completing portions of the build. Appreciate it!

Nice build and attention to detail. You can have a tune for SQ and tune to get done with that bass.