Ferrari F355 GTS
Custom Subwoofer Enclosure
A factory system built for two channels, reengineered to fit a third
The F355 GTS left the factory with mid-bass drivers in the front doors and tweeters near the dash vents. It was a system built for clarity, not low end. There was never a third speaker location designed into the car, let alone room for a subwoofer, and nothing in the cabin was engineered to accommodate one later.
A bespoke enclosure engineered to occupy the space between the two seats, built to the car's exact geometry through a full scan-to-CNC process and test-fit in the car to confirm the fit, with zero modification to the original bodywork or the factory-installed components around it.
No Factory Precedent, No Room to Spare
The F355 GTS's factory audio system was never meant to do more than it does: mid-bass drivers in the front doors and tweeters near the dash vents, with no low-end presence and no provision anywhere in the cabin for a third speaker. The client wanted a fuller, more immersive sound without altering the car's original character.
As a mid-engine car, the F355 GTS doesn't have the rear cargo area a front-engine platform would offer. The engine bay sits directly behind the seats, which ruled out the kind of trunk-mounted enclosure that's a straightforward solution in most vehicles. That left the console area between the two seats as the only realistic option, a space shared with the shifter mechanism, handbrake, and structural tunnel running the length of the cabin.
Every surface in that area is compound-curved or load-bearing, with no flat panel available to mount against. A generic enclosure, even a well-built one, wasn't an option. Anything that didn't conform exactly to the car's real geometry risked rattling loose, interfering with the shifter's range of motion, or requiring modification to original bodywork the client wasn't willing to accept. Any deviation between the scan and the finished parts would show up immediately: either as a gap against the trim, a knock against the shifter's travel, or an enclosure that simply wouldn't sit where it needed to.
There was an acoustic constraint layered on top of the physical one: the driver needed a sealed internal volume in a specific range to perform as designed, which had to be balanced against an external footprint that couldn't grow past what the console area could physically accommodate.
- No factory speaker location behind, beside, or between the seats
- Extremely limited volume in the space between the console and the seats
- Zero tolerance for modifying the car's original bodywork
Built to the Car, Not to a Template
We started with a full 3D scan of the interior, focusing on the space between the seats, capturing the exact contours of the console, seat rails, and surrounding trim. That scan held to a surface accuracy of 0.050mm, precise enough to build directly to the car's real geometry without a round of trial-fit rework. It became the foundation for a CAD model of the enclosure, engineered around an Audison Prima APS 8 D subwoofer, an 8-inch driver built for a shallow mounting depth well suited to a space this tight, and shaped to nest directly against the car's real surfaces rather than a generic mounting bracket.
Output from a subwoofer is largely a function of how much air the driver can move within its enclosure, so hitting that internal volume target mattered as much as matching the car's external contours. The CAD model was broken down into nine individual parts, each one shaped to route around the shifter mechanism, seat rails, and structural tunnel while still forming a sealed enclosure once assembled, a direct result of building to the car's actual geometry rather than a simplified box shape.
Each piece was CNC-routed from MDF to hold tight tolerances between mating surfaces, since even small gaps at this stage would compound into a poor fit once assembled. Once the pieces were cut, the enclosure was assembled and test-fit directly in the car to confirm it matched the F355 GTS's contours exactly: clearing the shifter's full range of motion, seating flush against the surrounding trim, and sitting stable under the kind of vibration a car cabin sees in daily driving.
- Full 3D scan of the mounting cavity between the seats
- CAD enclosure model built to the car's real geometry, not a generic template
- Parts CNC-routed from MDF and assembled to spec
Finish-Ready, Built to Fit
The finished enclosure was test-fit directly in the car and confirmed exact to the F355 GTS's contours, with zero modification to the original bodywork. Kemperle Industries' scope covered design and fabrication through to a finish-ready enclosure; upholstery and final trim work were handled separately.
Handing off a finish-ready enclosure, rather than a fully upholstered one, gave the client the flexibility to match the box's surface to the rest of the cabin's trim and stitching exactly, work best left to a specialist familiar with the car's specific leather and color match rather than bundled into the fabrication scope. The nine-piece assembly holds its shape and fit regardless of what finish goes over it, since the structural work was already locked in during CNC fabrication and test-fitting, not left for someone downstream to correct.
For a car with the collector significance of an F355 GTS, avoiding any modification to the original structure wasn't just a design preference. It was the only acceptable outcome. The result gives the F355 GTS the fuller, more immersive sound the factory system couldn't deliver, without compromising the car's structure or original character. It's a representative example of Kemperle Industries' aftermarket automotive fabrication work, solving problems the factory never accounted for, built to hold that fit for the long run.
- Custom enclosure built to fit precisely between the two seats
- Zero modifications to the car's original bodywork
- Test-fit confirmed exact to this car's contours
- Delivered finish-ready for upholstery
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