Original US Importer
Goldhorn DSP. We import, tune, support, and warranty the line directly.
SQ judge on staff
IASCA National and MECA World Sound Quality Championship titles. Judging since 2019.
Hands-on expertise
In mobile audio since 1985. We run this gear in our own vehicles.
Fast shipping from TN
Real inventory in Tullahoma. Call or text 707-999-3071.
Where do you want to start?
Five ways into the catalog. Pick the one that matches what you are actually trying to solve.
Vehicle Specific Series
Ford F-150 and F-250 behind-seat enclosures
Direct-fit behind the rear seat, cut on our routers to the cab dimensions rather than trimmed down from a universal box. Loaded options ship with the driver already mounted and wired. Choose the enclosure by cab year range, not by guesswork.

F-150 Behind Seat Single 10" (2015-2023) Subwoofer Enclosure | Super Duty Model
$ 359.99

F-150 Behind Seat Single 10" (2015-2023) Behind-Seat Subwoofer Enclosure | PR Edition with Passive Radiator
$ 449.99

2024-2026 Ford F-150 Behind-Seat Single 10" Enclosure – Loaded with JL Audio 10TW3-D4
$ 949.99

2024-2026 Ford F-150 Behind-Seat Single 12" Enclosure – Loaded with Wavtech thinPRO 12
$ 1,099.99
Built in Tullahoma. Engineered to outlast the vehicle.
Every Proline X enclosure is CNC-cut in our Tennessee facility from Langboard Elite MDF, the densest, most acoustically inert substrate available. No outsourcing. No shortcuts. No compromises.
Founded 2014
Built by a competitor, for people who care how it sounds
Scott Welch started in mobile audio in 1985 and founded Audio Intensity in December 2014. He holds IASCA National and MECA World Sound Quality Championship titles, and has judged SQ competitions since 2019. He is also the Original US Importer of Goldhorn DSP, which means we import, tune, support, and warranty that line ourselves rather than passing you to a distributor.
Proline X enclosures are manufactured here in Tullahoma. CNC cut on ShopSabre routers from Langboard Elite MDF, terminal cups printed in house in ABS-GF on Bambu Lab H2S printers, acrylic inserts and gaskets cut on a Full Spectrum Pro48 100W CO2 laser. Two year warranty. If something is wrong with a box, it comes back to the people who cut it.
Questions before you buy? Call or text 707-999-3071, or use the contact page.
Run the numbers before you buy
Free calculators we built for our own bench work. No signup, no email capture. If the math says your driver wants a different box than the one you were about to order, better to find that out now.
EBP Calculator
Fs divided by Qes. Under 50 wants sealed, 50 to 100 is transitional, over 100 wants ported.
Subwoofer Airspace Calculator
Net internal volume from external dimensions, with material thickness and driver displacement removed.
Sealed Box Calculator
Model Qtc and F3 for a sealed alignment before you cut anything.
Subwoofer Tuning Tool
Port length and tuning frequency for a vented box at a target Fb.
Every guide and calculator lives in the car audio resource library.
What high end car audio actually means
High end car audio is not a price bracket. It is a system where every stage is matched to the one before it: a driver chosen for the airspace it will actually live in, an enclosure built to that driver's published parameters, amplification sized to the driver's real power handling, and processing that corrects for where you are sitting. Skip any one of those and the expensive parts cannot do their job.
Why we manufacture our own enclosures
Most retailers sell you a driver and a box that were never designed together. We cut ours in Tullahoma on ShopSabre routers from Langboard Elite MDF, sized to the driver going in it. Vehicle specific models are cut to the cab rather than trimmed down from a universal shell, and loaded models ship with the driver already mounted and wired. Every Proline X enclosure carries a two year warranty and comes back to the people who built it. The full range is in the subwoofer enclosure catalog and under Proline X.
Processing is where most systems are won or lost
A car is a bad room. Seats are off axis, path lengths differ by a foot or more between left and right, and glass and plastic do unhelpful things above 2 kHz. Time alignment and EQ fix problems that no amount of driver budget will. We are the Original US Importer of Goldhorn DSP, so tuning questions come back to us rather than to a distributor.
Working out what you need
If you are not sure where to start, the calculators above will tell you whether your driver wants a sealed or ported alignment and how much airspace it needs. The written guides go deeper on enclosure design, amplifier matching, wiring, and DSP tuning in the resource library. If you would rather just ask, call or text 707-999-3071 and you will get someone who has built the box.
Car audio questions we get asked
Get expert answers to the most common car audio questions. From installation guidance to technical specifications, our team provides the knowledge you need to make informed decisions about your vehicle's audio system.
What makes Audio Intensity different from other car audio retailers?
We manufacture, we do not just resell. Proline X subwoofer enclosures are CNC cut in our own shop in Tullahoma, Tennessee on ShopSabre routers from Langboard Elite MDF. Scott Welch has been in mobile audio since 1985, holds IASCA National and MECA World Sound Quality Championship titles, and has judged SQ competitions since 2019. We are also the Original US Importer of Goldhorn DSP, which means we import, tune, support, and warranty that line directly.
What counts as high end car audio?
A system where the parts were selected to work together rather than bought individually off spec sheets. In practice that means the subwoofer is matched to an enclosure built for its published Thiele Small parameters, the amplifier is sized to the driver's real RMS handling rather than its peak rating, and a processor corrects for seating position and path length differences. A moderately priced system designed properly will beat an expensive one that was not. Browse the high end car audio catalog for the amplifiers, processors, and drivers we run at the reference end.
Which car audio brands do you carry?
Arc Audio, Audiomobile, Audio Wave, Crescendo, Goldhorn DSP, Image Dynamics, JL Audio, Karma Mobile Audio, Prodigy Audio, Tru Technology, US Acoustics, and Wavtech, plus our own Proline X enclosure line. The catalog is deliberately narrow. We stock what we would run ourselves rather than everything a distributor will sell us. The reference tier from those high end car audio brands is collected on one page.
Do you make subwoofer enclosures for the Ford F-150 and F-250?
Yes. We build behind-seat direct-fit enclosures for the 2015 to 2023 F-150 and 2017 to 2023 F-250, and for the 2024 to 2026 F-150. Single 10 inch, dual 10 inch, single 12 inch, and passive radiator versions are available, and several ship loaded with the driver already mounted and wired. Check the year range on the listing before ordering, because the cab changed between platforms and the boxes are not interchangeable.
Are your enclosures built to order or off the shelf?
Both. Stocked models ship from Tullahoma, usually the same or next business day. Because we run the routers ourselves we can also cut a variant that is not listed, such as a different net volume or a different driver cutout. Call or text 707-999-3071 to talk through a one off.
Should I run a sealed or a ported enclosure?
Let the driver decide. Divide the driver's free air resonance by its electrical Q, which gives you the efficiency bandwidth product. Under 50 the driver generally wants a sealed box, 50 to 100 works either way, and over 100 it wants a vented box. Sealed gives you a shallower rolloff and better transient behavior in a smaller footprint. Ported gives you more output near the tuning frequency at the cost of box size and a steeper rolloff below it. Our EBP calculator will run the number for you.
Do I actually need a DSP?
If you care about staging and tonal balance, yes. A car puts you off axis from both front speakers with path lengths that can differ by more than a foot, which smears the center image and creates cancellation you cannot EQ away. Time alignment fixes that. Once arrival times are corrected, EQ can address the response problems that are genuinely acoustic. A DSP will usually do more for perceived quality than the same money spent on larger speakers.
Where do you ship from and how fast?
Everything ships from our shop at 122 Turkey Creek Church Rd, Tullahoma, TN 37388. In stock items generally go out the same or next business day. We are reachable Monday through Friday, 9am to 5pm CST, at 707-999-3071 or contact@audiointensity.com.













