What's the difference between Performance and Performance Optimized?

The Performance Series uses universal tuning targets that work across multiple drivers in the same diameter. The Performance Optimized Series tunes each enclosure to a specific driver, with internal volume, port dimensions, and baffle cutout matched to that woofer's exact parameters. Performance Optimized produces more output and better acoustic loading for the specific driver it's built for. Performance is more flexible if you might swap drivers later.

Will a Performance Optimized enclosure work with a different driver than the one it's labeled for?

Technically yes, mechanically no. The baffle cutout is machined to the labeled driver's exact mounting dimensions, so a different driver may not fit cleanly without modification. The internal volume and port tuning are also calculated for the labeled driver, so swapping in a different woofer puts the enclosure outside its design parameters. If you want a Proline X enclosure that supports multiple drivers in the same size class, the standard Performance Series is the better choice.

Why don't these enclosures include polyfill, prewiring, or rubber feet?

Each is a deliberate omission for output-focused installs. Polyfill alters port tuning accuracy in ported configurations. Prewiring locks the installer to a specific impedance configuration before the wiring strategy is set. Rubber feet aren't relevant when the enclosure is being mounted in a vehicle. The Performance Optimized Series ships ready for the installer to finish in line with the system's specific tuning and wiring requirements.

How do I choose between sealed and ported in this series?

Sealed if accuracy and tight transient response are the priority, and if the available install space favors a smaller cabinet. Ported if maximum output at the tuning frequency is the priority, and if the install has the space to accommodate a larger box. Both alignments are properly tuned to the specific driver in this series, so the choice comes down to build goals rather than enclosure quality.

What construction does Proline X use?

Cabinets are built from Langboard Elite MDF (48.5 lb/ft³ density, 200 psi internal bond strength), the highest-grade MDF available for enclosure construction. Panels are joined with Dado and V-Groove cuts that mechanically interlock at each intersection before bonding. Every enclosure is CNC-cut on ShopSabre routers in our Tullahoma, Tennessee facility. Not imported, not outsourced.

Does this series include the screws to mount the driver?

Screws are not supplied with Performance Optimized enclosures. Driver mounting hardware varies by manufacturer (machine screws into T-nuts, wood screws into baffle, etc.) and the right hardware depends on the specific driver being mounted. Use the hardware specified by the driver manufacturer.

What measurements should I confirm before ordering?

Confirm driver mounting depth and terminal clearance. Use the downloadable cutout template to verify that the faceplate and mounting holes match your driver. If your driver has a nonstandard basket or offset mounting holes, measure the bolt circle and overall flange diameter, and send those dimensions to support. That prevents surprises at install and avoids returns due to fitment mismatch.

Why do you ship without mounting hardware and terminals?

We leave hardware out because installers use a wide range of fasteners and terminal styles depending on the driver and vehicle. Supplying a universal kit can create more problems than it solves. Instead, we offer a recommended hardware bundle that includes gasket tape, terminal cups, stainless screws, and lock washers. Add the bundle at checkout, and the product page will show the exact contents and suggested torque values for common driver baskets.

How do you control port velocity, and why does it matter?

Port velocity is measured during bench testing at target SPL using calibrated sensors. High port velocity causes audible port noise and reduces linear output at high drive levels. We size the port area and length to keep the velocity below thresholds appropriate for the driver and target output. If you plan extreme SPL runs, request the measured port velocity plots for your driver and enclosure pairing so you can confirm the design meets your goals.

Can I request a custom finish or a different cutout?

Custom faceplate finishes and alternate cutouts are available for production runs. Provide interior color samples or a driver cutout drawing, and we will quote lead time and cost. For one-off custom work, expect a short lead time for template approval and a small tooling fee for nonstandard cutouts.

Subwoofer enclosure banner image with sub enclosures from proline x

Made in the USA

Proline X Performance Optimized Series Enclosures

CNC-cut Proline X subwoofer enclosures across sealed, ported, and vehicle-specific configurations.

Best for Image Dynamics IDQ

Subwoofer in a black enclosure on a gray background

Proline X

Performance Optimized Sealed 10" Enclosure | Image Dynamics IDQ 10

Performance Optimized for the IDQ10 V4 specifically. Dimensions, port, and baffle cutout calculated for IDQ's Thiele-Small parameters.

$ 199.99

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Best for JL Audio W3 Series

Proline X

Proline X - Performance Optimized Enclosure for JL 10 W0/W1/W3

Ported 10 inch JL Audio W0/W1/W3 enclosure. Driver-matched port tuning for the W3 SQ-grade install.

$ 219.99

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Best for Sony Mobile ES

Proline X

Performance Optimized Sealed 10" Enclosure | Sony ES

Sealed 10 inch Sony XS-W104ES enclosure. Driver-matched fitment for the closeout-priced Mobile ES driver.

$ 199.99

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Tuning Frequency 32Hz - 38Hz

Material Langboard Elite MDF

Power Rating Driver Dependent

Ideal For Woofer-Specific Fitment

Shop the Lineup

Proline X PO 10-S W P3

Performance Optimized Wedge Sealed 10" Enclosure | Rockford Fosgate P3D2-10

$ 269.99

In stock and ready to ship!

Performance Optimized Dual Sealed 10-inch Enclosure Image Dynamics IDQ 10 - Proline X Subwoofer Enclosures for car audio systems

Proline X PO ID 10D-S

Performance Optimized Dual Sealed 10" Enclosure | Image Dynamics IDQ 10

$ 329.99

In stock and ready to ship!

A black fabric-covered subwoofer enclosure box with a circular wood-grain front opening, showing internal wiring and a 1.0 ft net, on a solid white background.

Proline X PO12-S SI BB

Proline X PO12-S SI | Single 12" Sealed Subwoofer Enclosure | Built for Stereo Integrity SQL

$ 299.99

In stock and ready to ship!

Proline X PO 10-S W GU

Proline X PO 10-S W GUS | Single 10" Sealed Wedge Subwoofer Enclosure | Built for ResoNix GUS-10

$ 279.99

In stock and ready to ship!

Proline X PO 10-S W T1

Performance Optimized Wedge Sealed 10" Enclosure | Rockford Fosgate T1D210

$ 279.99

In stock and ready to ship!

Proline X PO 12-S W P3

Performance Optimized Wedge Sealed 12" Enclosure | Rockford Fosgate P3D2-12

$ 279.99

In stock and ready to ship!

Performance Optimized Wedge Style Ported 10 inch Subwoofer Enclosure Prodigy NB2 10 - Proline X Subwoofer Enclosures for car audio systems

Proline X PO10-P W NB2

Proline X Single 10" Ported System | Loaded with Prodigy NB2

$ 289.99 $ 319.99 9% OFF

In stock and ready to ship!

Proline X PO 12-S W W3

Performance Optimized Wedge Sealed 12" Enclosure | JL Audio 12W3v3

$ 289.99

In stock and ready to ship!

Proline X PO 12-S W TW

Performance Optimized Wedge Sealed 12" Enclosure | JL Audio 12TW3-D4

$ 289.99

In stock and ready to ship!

Performance Optimized Wedge Sealed 12 inch Enclosure for Kicker Comp VX 12 - Proline X

Proline X PO 12-S W Co

Performance Optimized Wedge Sealed 12" Enclosure | Kicker Comp VX 12

$ 289.99

In stock and ready to ship!

Proline X Performance Optimized dual sealed enclosure for Arc Series subwoofers, front view of both cutouts.

Proline X PO ARC 10D-S

Performance Optimized Dual Sealed 10" Enclosure | Arc Audio 10" Arc Series

$ 329.99

In stock and ready to ship!

Proline X M10-S NB3 D4

Proline-X Sealed 10" Enclosure – Loaded with Prodigy Audio NB3

$ 299.99 $ 329.99 9% OFF

In stock and ready to ship!

Proline X PO 12-S W GU

Proline X PO 12-S W GUS | Single 12" Sealed Wedge Subwoofer Enclosure | Built for ResoNix GUS-12

$ 299.99

In stock and ready to ship!

Proline X PO 12-S W ID

Performance Optimized Wedge Sealed 12" Enclosure | Image Dynamics IDQ 12

$ 299.99

In stock and ready to ship!

Proline X PO 12-S W W6

Performance Optimized Wedge Sealed 12" Enclosure | JL Audio 12W6v3

$ 299.99

In stock and ready to ship!

Performance Optimized Wedge Sealed 12 inch Enclosure for Kicker CompQ 12 - Proline X

Proline X PO 12-S W Co

Performance Optimized Wedge Sealed 12" Enclosure | Kicker CompQ 12

$ 299.99

In stock and ready to ship!

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Built Different. Built Better.

Every Proline X enclosure is manufactured in our Tullahoma, Tennessee facility using materials and construction methods that most enclosure brands don't touch.