07/19/2026
Another day, another Tesla, that’s life here in the SF bay area. 😊
Having said that, this build was something pretty special, this 2025 Model 3 Highland is from a long term customer of ours from Southern California. Previously, he had an OEM+ system installed into the vehicle and was not satisfied with it, compared to the past projects we have done for him, it simply fell short.
Upon inspection, we discovered the OEM+ project was botched, wrong speakers installed and pieces missing. So it was good to start fresh.
I handled most of this project with support from Jesse on the underhood wiring.
The goals of this build is to achieve a very nice level of sound quality with less restraint on budget. The goal is to end up with a daily driver that sounds fantastic but still retains a bit of daily usability. To accommodate the higher end equipment, he was willing to sacrifice a bit more trunk space than our normal in the well model 3 builds, but he wanted to keep the ability to pass long items through via the backseat fold down. The overall theme is to have it clean, durable, not much emphasis on show, and most importantly, sound excellent across a wide genre of music.
For signal, as is the norm with all of our Tesla builds, is a two fold affair. The OEM signal were tapped and routed to the Mosconi aero812 DSP, while a secondary, pure source in the form of a Mosconi MOS BTS LD4C direct streaming module was utilized as well. Both route through the dsp and all 12 channels of outputs were utilized (more on this later)
For front stage, as we have done several Gladen speaker builds for him in the past, we once again chose them. A set of Gladen Pro midranges were installed into the stock lower door location with full sound proofing of the door. While a Pro midrange and an aerospace tweeter was molded into the A pillar. While the stock locations in the Model 3 is serviceable, he wanted to take it up a notch so those two drivers were molded into the pillars. As the Pro midranges do not come with grilles, we instead went with the aerospace midrange grille and matched the appearance with an aerospace tweeter. The aerospace set on its own, is severely limited on inventory these days due to global supply chain issues. But I feel the newly released pro set is more than a match for the more than decade old Aerospace series.
To add some additional impact as he has had a front subwoofer car from us before, we chose a single Helix I5 8” woofer, fitted into a front passenger footwell enclosure, to augment the upper bass/lower midbass region without adding too much energy. Due to the shallowness of the drier and the thick amount of foam under the passenger side floor, I was able to build an enclosure that took up less than 2” of legroom on the upward sloping portion of the floor. A magnetic mesh/mdf grille, wrapped in black carpet, protects the woofer. Sitting in the passenger seat, it’s hardly noticeable.
The stock center, rear door and rear deck speakers were repurposed, processed and powered by aftermarket amps to provide a more solid anchoring of the center image, ambience and sense of space for the entire car. This is how all 12 channels of the DSP came to be utilized. With front active 3 way, front impact, center, rear doors, sub, and rear deck surround run in mono. I think this is only the 3rd time I have used up this many channels on a DSP.
For subwoofer, the goal was still to retain as much trunk space as possible, and this is where the ultra-small box performance of the Wavtech Thinpro 10s came in to play. They each went into a 0.35 cubic foot sealed enclosure and worked beautifully within.
For amplifiers, the customer has had almost the entire lineup of our offerings in the past, so we decided to use the Arc Copper series to power the main drivers in the system. With two 4.2s powering the front stage, the center and the impact driver, and a 6.2 on the two Wavtech subs. Additionally, an Arc audio x2 450.4 runs the rear door and rear deck peripheral speakers.
One of the weak points of the model 3 has always been bass response from a trunk mounted sub and is the reason why we have frequently done a front sub in these cars. In this one, I was shocked to discover that while the rear deck had two “subwoofers” on the metal deck, there was NO OPENING on the plastic rear deck cover! I am not sure if I have ever seen this done before in a car, but I was not about to let that stand. After discussing various options with the customer, including a nice custom grille on top of the deck, it was decided to save the cost there as this is purely a daily driver, and do two simple off the shelf grilles to provide bass pass through. I found some two piece mesh grilles online and integrated them into the rear deck cover after cutting out the holes. I also laid down a piece of breathable carpet under the grilles so neither the hole openings nor the metal deck can be seen. Would I have preferred a fully custom grille from a cosmetic standpoint? Yes, but I also understand the reasoning to save costs on items that do not factor into the overall sound quality of the vehicle.
For the trunk, I pride myself on being able to stuff a 10lb package into a 5lb hole, but this ability was truly put to the test on this project. Not only is my goal to fit them in properly spaced locations, but I also wanted to make sure everything is relatively easy to service and replace should an issue arise. I think it is always a good idea to make things serviceable to the best of my ability as no system, no matter how well installed, is immune to equipment issues in the long run.
As previously mentioned, this build is well beyond the usual Model 3 projects we have done, which locates everything in the storage well under the floor.
For the well, I built a two tiered structure with a bottom portion acting as main support, housing two XS Power RSV lithium batteries that insulates the stock 16v system from the demands of our system, acting as an additional safety layer. Also located on this bottom portion if the X2 450.4 amp and the Mosconi DSP. This bolts to the car via a series of rivetnuts and drilled and tapped threaded holes on the side beams.
The three main amplifiers is housed in a rack on top of the front portion of the trunk floor. With their own supports. The bottom portion has an upward sloped section that buts up to the top floor section, providing me with additional space that I used distribution, circuit breakers and barrier strips.
The sub enclosure, with two separate sealed chambers, is designed to simply drop down onto the bottom structure, located via pin dowels, and bolted in place via threaded inserts. It even has two handle bars on the sides to allow easy pick up and drop down. Armed only with a Philips screw driver and an extension, I can remove this enclosure within 60 seconds to gain access to the equipment below.
For trim around the equipment, I decided to do something different than our normal vinyl trim. Instead, I wrapped the panels in this space age looking honey comb vinyl wrap, I feel like it’s a pretty good match for a new tesla, which is sort of a space age car. The main difference here is, thin vinyl wrap reveals every little imperfection on the surface, so I taped off the visible section, high build primered it, and sanded it back down smooth for the wrap.
The top cover is also a two piece design. The cover over the subs is a simple cover that sits at the angle of the stock floor panel. The bigger cover over the amps though, was a bit more time consuming. The angle of the sides of the stock carpet does not match the floor orientation and changes 3 times as it goes from the front to the back of the car, dropping down as it travels backwards. Thus, I had to design a cover with 3 separate sections of side walls so it matches that shape. At the front, I put down a 45 degree slant so the top cover meets the lower floor at an angle versus an abrupt ledge. I 3D printed a tesla logo to put on this slanted surface for some additional visual pop.
Last thing was making the breathable grilles and also a thin panel at the front seat opening area, also wrapped in the same honeycomb wrap, to hide the bare wood and wiring.
Front the first time I powered up this system, I knew it was going to be really really good. As with zero EQ on it, it already sounded very pleasant. After some tuning with myself and our guy mike, I am pretty confident to say this is perhaps one of the top 5 best sounding cars we have done.
There was virtually no weak point in the sound quality. Imaging and staging was super precise, pillar to pillar, to the edge of the windshield, and about 8 inches off the dash. It’s among the most believable front stages I have done in a while. Keeping in mind that I don’t tune for clinical sound quality competition type of front stages anymore, and there will be more rears added into the mix, but for an everyday listening type of experience, this is spectacularly precise. The front impact woofer did its jobs very nicely, playing 65hz to 110 hz, it augmented the impact portion the bass without any pulling of the stage. It is still hard to believe that a subwoofer in such a small enclosure can deal out this much smooth low frequency response, but the two Wavtech Thinpro 10s did their job very well playing 65hz and down. The two grilles I installed into the rear deck really helped with bass pass through in this car. The subs provided plenty of deep bass without ever making their location known and just filled in things nicely.
The front stage, with the caliber of speakers used, was really really good from a tonality standpoint. From midbass to the highs it’s just detailed, airy, and smooth. After some tweaking I didn’t find any songs (and I played through maybe 50 or more) that I felt brought out anything negative in the system. It just really nice sounding regardless if it is jazz, rock, classical, hip-hop, or whatever. This fits very well with the broad listening tastes of the customer.
Thus concludes one of the two (not counting those Dolby Atmos mega projects) biggest Tesla builds of my career. This one focused on more delicate and broad music while the other big Model 3 build was tuned more for volume, output and bass. I used to hate working on Teslas due to their poor interior build quality, but I have to say, they have improved a lot over the years and I would not mind doing another such build in the future.
Thanks for reading, and as usual, please check out the individual pictures for a more detailed explanation of the build process.
Cheers,
Bing
