Proline X enclosures come in six series: Performance, Professional, Micro, X, Vehicle Specific, and Loaded. They all share the same foundation, 3/4" Langboard Elite MDF cut on ShopSabre CNC routers, but each is built for a different driver and install. The right one comes down to three questions: do you have a specific high-excursion driver, how much mounting depth does your vehicle allow, and do you want the box loaded with a driver or empty.
- All six series share the same build: 3/4" Langboard Elite MDF, ShopSabre CNC cutting, composite terminal cup, copper ring terminals, 12-gauge OFC, stainless hardware, and a 2-year warranty
- Performance is the general-purpose pick. Professional is driver-specific with a double-layer baffle for high-excursion subs
- Micro is shallow-mount sealed for depth-limited installs. Vehicle Specific is contoured to a truck or SUV behind-seat or under-seat space
- X Series is built to the dimensions of Kicker Solo-X drivers. Loaded ships pre-loaded with a matched driver, ready to mount
- Pick by driver, mounting depth, and whether you want it loaded. Sealed boxes ship with polyfill already installed
This is the series guide in our how a CNC subwoofer enclosure is built series. For the material every series is cut from, see what Langboard Elite MDF is.
Which Proline X Enclosure Series Is Right for You?
Start with three questions: what driver, how much depth, and loaded or empty. A common driver with normal mounting depth goes in a Performance box. A specific high-excursion driver you want maxed goes in a Professional box. A shallow space takes a Micro or a Vehicle Specific box. The table below maps each series to what it is built for.
| Series | Best for | Construction note |
|---|---|---|
| Performance | Common driver, sealed or ported, no special fitment | V-groove and dado joinery |
| Professional | A specific high-excursion driver you want at full output | Double-layer baffle, threaded inserts to the bolt pattern |
| Micro | Depth-limited installs that still need a sealed box | Stack-fab with dowels, 8/32 threaded inserts |
| X | Kicker Solo-X drivers | Built to the Solo-X dimensions and mounting |
| Vehicle Specific | Truck or SUV behind-seat or under-seat space | Contoured to the vehicle |
| Loaded | A turnkey box and driver, ready to mount | Pre-loaded and wired, matched driver |
What Do All Six Series Have in Common?
The same foundation runs through every series. Each box is cut from 3/4" Langboard Elite MDF on ShopSabre CNC routers, fitted with a Proline X terminal cup molded from ABS and carbon composite, copper ring terminals, and 12-gauge OFC pre-wired to the driver location. Hardware is stainless. Sealed variants ship with polyfill already installed. Every series carries a 2-year warranty.
So the choice between series is never about whether the box is built right. It is built right across the board. The choice is about fit and intent: which driver, how much depth, and whether you want it loaded.
How Do the Six Series Differ?
Performance Series
The general-purpose line, built with V-groove and dado joinery and sized for common drivers and install spaces. If you have a standard sub and normal mounting depth and just want a properly built sealed or ported box, this is the default. Shop the Performance Series.
Professional Series
Driver-specific boxes built to a particular subwoofer's published parameters, with a double-layer baffle as the minimum and threaded inserts matched to that driver's bolt pattern. This is the series for a known, high-excursion driver you want pulled to its full potential. Shop the Professional Series.
Micro Series
Shallow-mount sealed enclosures for tight spaces, built with stack-fab construction and dowel reinforcement, with 8/32 threaded inserts on the backside of the baffle for machine-screw mounting. Built for depth-limited installs that still need a rigid, sealed box. Shop the Micro Series.
X Series
Enclosures built for the dimensions and mounting of Kicker Solo-X drivers. We build the box to fit these drivers. We do not sell the drivers, and there is no affiliation implied. If you run a Solo-X, this is the enclosure side handled correctly. Shop the X Series.
Vehicle Specific Series
Boxes contoured to a specific vehicle, usually behind-seat or under-seat truck enclosures that work around window motors, vents, and the cab wall to use the available space without giving up storage. Shop the Vehicle Specific Series.
Loaded Series
Comes pre-loaded with a driver, built and wired so it is ready to mount and connect, with the same V-groove and dado construction as the Performance line. The turnkey option when you want the box and driver matched and done. Shop the Loaded Series.
Which Series for a Tight Truck or Under-Seat Install?
Mounting depth decides this. Many late-model trucks leave only 2 to 4 inches behind the seat or under it. A standard sealed box will not fit. Aftermarket subwoofer mounting depths run from about 2.5 inches for shallow-mount drivers up to 7 inches or more for deep competition subs, so the box and the driver have to be chosen together for the space (Crutchfield).
Chart: Typical subwoofer mounting depth by driver type (inches)
Source: typical aftermarket mounting-depth ranges (Crutchfield). Always measure the real available depth in your vehicle.
For a depth-limited spot where you are bringing your own shallow driver, the Micro Series is the call: a rigid, sealed, shallow box. For a truck where you want the enclosure shaped to the cab, the Vehicle Specific Series is contoured to that vehicle's behind-seat or under-seat space. If you would rather not source the driver separately, a Loaded box arrives matched and wired.
One more decision sits underneath all of this: sealed or ported. Sealed favors tight, accurate output. Ported favors more low-end volume and extension (SVS Sound). Work it from your driver's parameters in sealed vs ported, by the numbers.
Frequently Asked Questions
What are the Proline X enclosure series?
What is the difference between the Performance and Professional series?
Which Proline X series is best for a truck?
Do Proline X boxes come with the subwoofer installed?
What is the X Series built for?
Not Sure Which Series Fits Your Build?
Send us your driver, your vehicle, and the available mounting depth, and we will tell you which Proline X series is the right path before you spend. We CNC every box in our Tullahoma, Tennessee shop.
Contact us with the details, or browse the full Proline X enclosures and subwoofer enclosures collections.
About the Author
Scott Welch is a Multi Time IASCA National and MECA World Sound Quality Champion, an active SQ judge since 2019, and the owner of Audio Intensity in Tullahoma, Tennessee. He cuts every Proline X enclosure on the shop's CNCs and tunes every customer system before it leaves. Audio Intensity is the original US importer for Goldhorn DSP and an authorized dealer for Prodigy, Crescendo, Image Dynamics, Wavtech, Tru Technology, and more.
