r/CarAV • u/rocketbunny_v4 • 6h ago
Build Log 2021 WRX SQ Build Log Part 2 (3 Way Front Stage, More ResoNix Deadening and Big 3 Upgrade)
Links to older build log posts:
- 2021 WRX SQ Build Log (Prep work: Sound Deadener)
- My Experience switching from SoundSkins Pro to ResoNix Sound Deadener
Since my last update I’ve been working on a bunch of different parts of the build, so here is what I've worked on since then...
Front stage
Some of my AudioFrog GB 3 way components and rear fill (GB10CF, GB25, GB60, GS62) had been sitting in their boxes for a couple months, so figuring out what my front stage was going to look like was the next thing on my list that I wanted to tackle.
Scanning and design
I bought a Creality Raptor 3D scanner and my plan was to model the dash pods and A pillars myself in Fusion 360. I kept putting it off because I never had the time after work, so I ended up reaching out to Matt Kim from Audio in Reach. I was familiar with his work and it’s what I was trying to draw inspiration from anyway.
I already had clean scan data of my dash corners and A pillars (one of the attached photos is the driver side pillar scan), so I asked Matt if he’d take it on for my GB10CF tweeters as long as my data was good enough for him. He normally handles everything from start to finish by sourcing your exact car locally, so that means scanning, designing, printing and wrapping. He said yes and I got put in his queue.
A pillars
A few months later it was my turn in the queue. He designed the pillars and sent me the Bambu print files, so all I had to do was print them in ASA.
The photos show how I put them together and blended them into the OEM pillars. I used CA glue to assemble the pieces, Bondo to blend them in and CA glue/plastic welds to fasten them. The GB10CF tweeters are held in with a machine screw in the back. Most importantly, it does not interfere with the safety functionality of the airbag, as it sits below where the curtain starts.
Dash pods
A few weeks later I asked Matt to get back in the queue for the dash pods and got a file ready to print the same way. He designed them so I only had to cut a small section out of the dash corner with his template to fit the GB25. The cutting was minimal and it does not impact the OEM mounting location.
They needed way less prep than the pillars. I just sanded them so the DAP Weldwood Landau Top & Trim adhesive would stick when I wrapped them.
They clip into place like an OEM part, using custom 3D printed clips that screw into the pod. If a clip breaks when I pull a pod off, I can just print a new clip instead of a whole new pod. The GB25 is held in with M3 heat inserts and screws.
Grilles and wrapping
The pillars and pods each have their own grille, and I wrapped them in Mellotone Premium Black Speaker Grille Cloth from Parts Express. The main thing to watch is keeping adhesive off the portian where the sound actually comes out.
If anyone’s doing something similar, the vinyl that matches the WRX dash is Softside Auto’s Nuance Ebony. I ordered a ton of samples and visited local upholstery shops to figure that out, so hopefully it saves someone the trouble.
How it turned out
Matt got the design exactly how I wanted it. It looks like it came from the factory and not like something added later. People who aren’t into audio don’t notice anything is different until it comes up in conversation. The photos show the before and after to illustrate the level of execution. There is also a photo that provides a look at the tweeters and midranges under the grille covers.
GB60 door adapters
In my first build log I used generic door adapters from Amazon for the GB60 midbass, and I wasn’t happy with them. The ResoNix CCF strips only had the outer edge of the GB60 to stick to. So I designed my own mount in Fusion 360 that fully surrounds the GB60 and gives the CCF strips enough flat edge to sit properly.
After printing them I sealed the adapters to the door with ResoNix CCF tape, and I put some 3mm CCF I had lying around between the adapter and the GB60.
Because the CCF tape was sitting on top of the deadener, the OEM Subaru speaker grommets wouldn’t stay in with all the extra material applying pressure. I fixed that with Hillman #452810 nylon nuts, which fit great and work way better than the OEM ones.
Sound deadening
Next I went back and deadened some some spots I’d put off.
I did the trunk lid with ResoNix Mega CLD and got about 80% of it covered. The narrow sections just weren’t reachable. There are wire harnesses inside for the latch and license plate lights, and anywhere they touched I put CCF down so they can’t rattle. I also added fiber mat to the trunk cover and lined the perimeter with CFF to cut down on noise.
I knew the roof wasn’t going to be fun. Getting the grab handles off took a while because a few of them didn’t want to unclip. I didn’t pull the headliner completely since I figured that would be more of a pain, between creasing it and dealing with the harnesses attached to it. I just dropped it enough to get working room. I started on a Friday night after work and kept going until it was done.
Nobody will ever see this area, same as everywhere else I deadened, but after all the work I’ve put in I wasn’t going to say “eh, good enough” and not care about how I applied it. After deadening it with Mega Cld, I lined it with 1 inch fiber mat, and the headliner went back up with no problem with the extra thickness added in between.
Alternator, battery and Big 3
The last part of this update is the electrical. I put in a 270 amp alternator from Singer Alternators to power my four Mosconi Pro amps (two Pro 4|10 and two Pro 1|10). It was a direct swap and took less than an hour, and my stock belt worked fine. I also switched to a Group 35 AGM battery from Odyssey.
To support the alternator, I had the shop (Car Audio Engineers) doing the amp, DSP and trunk floor install also do the Big 3. I designed a fuse bracket and had SendCutSend laser cut, bend and powder coat it. I wanted the shop to have a clean spot for the fuses that looks like it belongs there. It's not visible in the photo but it has a 90 degree flange that sits behind the battery tiedown bracket to help it stay in place without rotating.
With the 0 gauge wire going to the battery terminal, the OEM positive terminal cover didn’t fit anymore. So I designed my own terminal cover and printed it in PC FR, which is a flame retardant polycarbonate which clips on like the OEM one.
Conclusion
At the time of writing the full build is complete, and I’m just waiting on a follow up appointment to get a extension card installed once it arrives. That will give me an extra digital coax input for my Fiio M11 Plus DAP. I’m planning another write up down the road that covers the amp rack, the trunk design and the ResoNix GUS, and finally getting to put the deadening through its paces. Most of the Sound Quality builds people post about are about other platforms, so hopefully it gives other WRX owners some ideas for their own cars.
Sound Equipment Used
Speakers
- AudioFrog GB10CF Tweeter
- AudioFrog GB25 Midrange
- AudioFrog GB60 Midbass
- AudioFrog GS62 Coaxials
- ResoNix GUS12D4 Subwoofer
- ResoNix PTR 10 inch front sub (pending)
Amps and DSP
Sources
Sound Deadening used
Outer Door
Inner Door
Door Card
Roof
Rear Deck Lid metal/plastic
Trunk
Trunk Lid
