Proline X PO 12D-S DFW MPS sealed down-fire wide enclosure for two Hertz Mille Pro MPS 300, 41 inches wide by 8.75 inches tall, feet add 1.75 inches of height.

Proline X PO 12D-S DFW MPS sealed down-fire wide enclosure, end panel with side-mounted terminal cup, 8.75 inches tall by 14 inches deep.

Proline X

Performance Optimized Down Fire Wide Sealed Dual 12" Enclosure | Hertz Mille Pro MPS 300

Q: Why is this dual cabinet 41 inches wide instead of 30?

Because some installs run out of height or depth before they run out of length. The standard Hertz Mille Pro MPS 300 Down Fire cabinet is 30 by 15 by 10.75 inches; this one is 41 by 14 by 8.75. Spreading the airspace along 11 more inches lets the cabinet stand 2 inches lower, and at 14 inches deep it is 1 inch shallower front to back, about the minimum a 12 inch frame needs.If you have 41 inches of run and height or depth is the limit, this is the shape. If length is the limit, the standard 30 x 15 is the better fit.

Q: How does this compare to the standard 30 x 15 Hertz Mille Pro MPS 300 enclosure?

Same driver, same construction, different shape. The standard box is 30 by 15 by 10.75 inches and holds 0.80 cubic feet net per chamber; this one is 41 by 14 by 8.75 inches and holds 0.807 cubic feet net per chamber.The airspace is matched, so the alignment is effectively the same. The choice is about the shape of your space: the standard box when length is limited, this one when height or depth is the limit and you have 41 inches of run.

Q: Should I use two S2 or two S4 drivers?

On this size the S4 is the better damped driver, with a free-air Qts of 0.42 against the S2's 0.51, landing at Qtc 0.810 per chamber versus 0.999. The S2 reaches deeper, F3 37.0 Hz against 39.4.This is the opposite of the 10 inch MPS 250, where the S2 is the tighter driver. Whichever you choose, use two of the same model; mismatched drivers between chambers will not track each other.

Q: How is this enclosure wired?

One side-mounted Proline X terminal cup with a single pair of posts, pre-wired in 12 gauge OFC to both driver positions in parallel. You do not wire the two chambers separately at the amplifier.Both MPS 300 models are single voice coil, so the load is set by the model: a pair of S2 drivers in parallel presents 1 ohm, a pair of S4 drivers 2 ohms. Confirm that against your amplifier's minimum stable load before powering the system.

Q: Why two separate chambers instead of one shared volume?

Two drivers sharing one sealed volume load each other: each driver's compression stroke becomes the pressure the other works against, which blurs the alignment either would have alone. A bonded full-height 3/4 inch divider gives each MPS 300 its own 0.807 cubic feet and its own polyfill.It also means the alignment on this page is the alignment in each chamber, not an average across a shared box, and the divider ties the walls together across the 41 inch span.

Q: Where is the terminal cup located on a down fire enclosure?

Side mounted, and one cup serves both chambers. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup regardless of alignment. On this cabinet that keeps the connection accessible with the enclosure installed, since both baffles face the floor. The cup is our Proline X ABS and carbon fiber composite unit, recessed, with stainless hardware, copper ring terminals, and pre-wired 12 gauge OFC.

Q: How is this enclosure built?

V-groove and dado joinery, CNC cut on ShopSabre routers from Langboard Elite MDF, which keeps both chambers airtight under sustained pressure cycling. The chamber divider is a full-height bonded 3/4 inch panel. Corners are square, the Down Fire series standard.Front baffles are double layer at 1.5 inches at both positions, outer layer machined as a flush recess, with two sets of 8/32 threaded inserts and stainless machine screws. Polyfill is installed as a light wall lining in each chamber. Assembled and inspected in Tullahoma, Tennessee.

Q: Are the Hertz MPS 300 subwoofers included with this enclosure?

No. This listing is for the enclosure only. Bring your own pair of Hertz Mille Pro MPS 300 S2 or MPS 300 S4. The cutouts and mounting depth are direct fit at both positions; use two of the same model.

SKU: PO 12D-S DFW MPS

QUICK SPECS

Alignment: 0.807 cu ft net per chamber, 1.615 total. MPS 300 S2 Qtc 0.999, Fc 47.0 Hz, F3 37.0 Hz; MPS 300 S4 Qtc 0.810, Fc 44.3 Hz, F3 39.4 Hz
Down Fire Wide: 41"W x 14"D x 8.75"H in down fire position, lower than the standard 30 x 15 (10.75 in)
Height Set By: the airspace, matched to the standard 30 x 15 box
Chambers: Two fully separate sealed chambers, 3/4" MDF full divider, one shared side-mounted terminal cup
Drivers: Pair of Hertz MPS 300 S2 or S4 (SVC), 500W RMS each / 1000W combined, 16.8mm Xmax, 3.465" mounting depth

Shipping Included No freight charges at checkout. What you see is what you pay.

Built in Tennessee CNC cut from 3/4" Langboard Elite MDF. V-groove and dado joinery.

Advanced Terminal Cup Built in-house. ABS/Carbon Fiber. Stainless steel hardware. Copper ring terminals.

$ 369.99

In Stock and Ready to Ship

Financing available. Choose Shop Pay Installments at checkout.

Performance Optimized Down Fire Wide Sealed Dual 12" Enclosure | Hertz Mille Pro MPS 300

$ 369.99

More enclosures cut for Hertz subwoofers: Hertz Subwoofer Boxes

Enclosure Type Sealed

External Dimensions 41" W x 14" D x 8.75" H (measured in down fire position, excludes standoffs)

Gross Volume 1.81 cu ft

Net Volume 1.615 total / 0.807 per chamber cu ft

Shipping Weight 49.4 lbs

Front Panel Thickness 1.5"

INSTALLER'S TAKE

Two MPS 300s at 0.807 net each, Hertz's own 22.7 liters per driver, in a cabinet 8.75 inches tall instead of 10.75. The standard dual was the tallest box in the Down Fire line; the wide one takes two inches off it on the same air.

Per chamber: the S2 lands at Qtc 0.999 with F3 at 37.0 Hz, the S4 at Qtc 0.810 with F3 at 39.4 Hz. On the MPS 300 the S4 is the better damped driver. That is the reverse of the 10 inch MPS 250, so do not carry the assumption over.

Use two of the same model. Both are single voice coil, so the load is set by the model: a pair in parallel through the cup is 1 ohm on S2s, 2 ohms on S4s.

1000 watts RMS combined. Hertz suggests a 15 Hz subsonic at 24 dB per octave; use it.

Product Details

Proline X Performance Optimized Down Fire Wide Dual 12" Sealed

Cut for a pair of Hertz Mille Pro MPS 300, S2 or S4

Down Fire WideV-Groove and DadoSeparate Chambers22.7 L Per Driver

0.807cu ft net each

0.999system Qtc, MPS 300 S2, per chamber

37.0 HzF3 rolloff, MPS 300 S2

8.75 incabinet height, excludes feet

The Down Fire Wide Format

Down Fire Wide is the same driver in a different shape. The standard Performance Optimized Down Fire cabinet for the Hertz Mille Pro MPS 300 is 30 by 15 inches. This one runs 41 inches wide by 14 inches deep: 1 inch shallower front to back and 11 inches longer.

Fourteen inches is not arbitrary. A 12 inch frame needs about 13 inches of baffle to sit on, so 14 is the practical minimum depth for this driver size. The Hertz Mille Pro MPS 300 frame measures 12.532 inches across and sits on the 14 inch deep baffle with about 0.73 inches of baffle fore and aft. Both positions are laid out along the 41 inch length.

Spreading the airspace along 41 inches instead of 30 means the cabinet does not have to climb to find it. This box stands 8.75 inches tall, against 10.75 for the standard 30 x 15 Hertz Mille Pro MPS 300 cabinet, both measured in the down fire position without feet. That is 2 inches lower.

Which one to choose. The standard 30 x 15 is the pick when length is limited. This one is the pick when height or depth is the limit and you have 41 inches of run. With the 1.75 inch feet installed this cabinet stands 10.5 inches, so measure for that.

Performance, Performance Optimized, and Micro

Proline X builds three tiers of Down Fire enclosure. The difference is not finish or materials, it is whether the cabinet was designed for a category or for a driver, and how much of the fitting work is already done for you.

	Performance	Performance Optimized	Micro Series
Fitment	Universal. Accepts any subwoofer that clears the published cutout and mounting depth.	Woofer specific. Cut for one named subwoofer, with cutout, mounting depth, magnet clearance and displacement drawn in CAD from that driver.	Woofer specific. Cut for one named subwoofer.
Footprint	Sized to the driver diameter. 24.5 by 13.5 inches on the 10 inch.	Shared 30 by 15 inch platform on most builds. Down Fire Wide variants like this one run long and shallow for under seat fitment.	Compact per driver footprint. 21.5 by 14.5 inches on the 10 inch.
Front baffle	Single, 3/4 inch.	Double layer, outer layer machined as a flush recess. 1.5 inch.	Double, 1.5 inch.
Driver mounting	Solid flange. You drill your own mounting holes.	8/32 threaded inserts, stainless machine screws included.	8/32 threaded inserts, stainless machine screws included.
Joinery	V-groove and dado, CNC cut.	V-groove and dado, CNC cut, perimeter cross brace.	Stack fab, dowel reinforced.
Published alignment	Modeled Qtc profiles across a range of drivers. No single response curve.	A real predicted Qtc and F3 for that exact driver, calculated from its own Thiele-Small parameters.	Target alignment described in the listing.
Carpet	Gray standard, black optional.	Plush black.	Plush black.
Warranty	1 year limited.	1 year limited.	2 years.

Feet ship with every tier, uninstalled on purpose. Mount them where your floor wants them for a down fire install, or leave them off and run the cabinet front firing or up firing. The orientation is yours to choose.

This page is a Performance Optimized enclosure. The cutouts, the cabinet height and the airspace all come from the Hertz Mille Pro MPS 300's own published numbers. A Performance box fits your subwoofer. A Performance Optimized box was built for it.

Built Around a Pair of MPS 300s

Both baffle positions are bored to the MPS 300's 283mm cutout, 11.14 inches, and the motor clears the top panel with 4.535 inches to spare, so the height of this cabinet is set by the airspace Hertz asks for, not by the 3.465 inch mounting depth.

Each MPS 300 carries 16.8mm of one way Xmax behind a 38mm voice coil and a high density flux ferrite motor, with a polypropylene cone. Power handling is 500 watts RMS and 1000 watts peak per driver, 1000 watts RMS across the pair.

The depth comes from a 24 Hz free air resonance paired with a 64.9 liter Vas on the S2, and 23 Hz with 62.1 liters on the S4. Each driver is sold as the MPS 300 S2 at 2 ohms or the MPS 300 S4 at 4 ohms, both single voice coil. Use two of the same model; mismatched drivers between chambers will not track each other.

Net Volume and Alignment

Each chamber holds 0.807 cubic feet net, 1.615 cubic feet net across both, from 1.81 cubic feet gross after the divider, the bracing and each driver's 0.08 cubic feet of displacement (estimated, no manufacturer figure).

Height is the free dimension. With the footprint fixed at 41 by 14, the cabinet height was solved to put each chamber on the same airspace as the standard 30 x 15 box, which holds 0.80 cubic feet net per chamber, and the motor clears the top panel with 4.535 inches to spare. Same air, same alignment, lower cabinet.

Computed from Hertz's published Thiele-Small parameters: MPS 300 S2: Qtc 0.999, Fc 47.0 Hz, F3 37.0 Hz; MPS 300 S4: Qtc 0.810, Fc 44.3 Hz, F3 39.4 Hz per chamber.

Each chamber matches Hertz's own sealed recommendation of 22.7 liters per driver. Pay attention to the model choice, because it reverses from the 10 inch MPS 250: on the MPS 300 the S4 is the better damped driver, Qts 0.42 against 0.51, with far more motor force, 18.7 T·m against 12.3. The S4 gives the more controlled alignment; the S2 reaches about 2.4 Hz lower with a modest lift at the corner.

True net, not marketing net. Internal volume is calculated from the machined cavity dimensions and the driver's displacement, not estimated from external dimensions minus wall thickness.

Two Chambers, Not One

This enclosure follows the Proline X standing design rule for dual sealed builds: two fully separate chambers divided by a bonded full-height 3/4 inch MDF panel.

Two drivers sharing one sealed volume interact acoustically. Each driver's compression phase becomes the pressure environment the other is working against, which smears transient response and blurs the alignment each would have on its own. A full divider removes that. Each Hertz Mille Pro MPS 300 gets its own 0.807 cubic feet net and its own polyfill.

On a 41 inch cabinet the divider does structural work as well, tying the front and rear walls together at the centre of the span. One shared side-mounted terminal cup feeds both driver positions.

Down Fire Wide Construction

Cut with V-groove and dado joinery on our ShopSabre routers from Langboard Elite 3/4 inch MDF, a dense 48.5 lb/ft³ board with a 200 psi internal bond and 410,000 psi MOE. Every panel joint is a machined interlocking groove that mechanically locks before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling. Corners are square on Down Fire cabinets.

The cabinet measures 41 inches wide by 14 inches deep by 8.75 inches tall, measured in the down fire position. Feet ship with the enclosure but are not installed. With the 1.75 inch feet on, the cabinet stands 10.5 inches, so plan the space around where you intend to mount them.

1.5 Inch Double Baffle

Two 3/4 inch layers laminated to 1.5 inches, with the outer layer machined as a flush recess so the driver bolts to the inner layer. 8/32 threaded inserts at the driver position, stainless machine screws included.

Separate Chambers

A bonded full-height 3/4 inch divider gives each driver its own 0.807 cubic feet net and its own polyfill, and ties the walls together mid span.

One Shared Terminal Cup

Proline X ABS and carbon fiber composite cup with stainless hardware and copper ring terminals, side mounted and pre-wired in 12 gauge OFC to both driver positions in parallel.

Polyfill Installed

Polyfill is installed as a light wall lining in both chambers to control internal reflections. It does not change the acoustic volume, so do not add more.

Power and Warranty

Each driver is rated 500 watts RMS and 1000 watts peak, 1000 watts RMS combined. Both models are single voice coil, so there is no coil wiring decision at the driver. One side-mounted cup feeds both positions in parallel: a pair of S2 drivers presents 1 ohm, a pair of S4 drivers 2 ohms. Confirm that against your amplifier's minimum stable load before powering up.

Hertz suggests a 15 Hz subsonic filter at 24 dB per octave and a 70 to 80 Hz low pass for sealed applications. The enclosure carries a 1 year limited warranty. Bring your own pair of MPS 300 S2 or MPS 300 S4; the drivers are purchased separately.

Cut for the Driver, Not the Catalog

Down Fire Wide, 41 inches long and 14 deep, cut for one driver model and built one at a time in Tullahoma, Tennessee. Questions on fitment or amplifier matching, call us at 931-563-5151.

Specifications

Series	Proline X Performance Optimized Down Fire Wide
Compatible Driver	Hertz MPS 300 S2 (2 ohm SVC) or MPS 300 S4 (4 ohm SVC). Pair required, direct fit
Enclosure Type	Sealed, dual driver, down fire, floor coupled
Chamber Configuration	Two fully separate chambers, full divider, single shared side-mounted terminal cup
Intended Fitment	Where height or depth is the limit and 41 in of length is available
Firing Direction	Down firing. Feet ship uninstalled, so front or up firing is also possible
External Width	41 in
External Depth	14 in
External Height	8.75 in, measured in down fire position, excludes feet
Installed Height	10.5 in with the 1.75 in feet installed
Standard 30 x 15 Equivalent	30 in W x 15 in D x 10.75 in H, 0.80 cu ft net per chamber
Internal Height	6.5 in
Internal Volume, Gross	1.81 cu ft total
Per-Chamber Net Volume	0.807 cu ft after displacement
Total Net Volume	1.615 cu ft
Height Set By	Airspace; the motor clears the top panel with 4.535 in
Alignment, MPS 300 S2 per chamber	Qtc 0.999, Fc 47.0 Hz, F3 37.0 Hz, anechoic
Alignment, MPS 300 S4 per chamber	Qtc 0.810, Fc 44.3 Hz, F3 39.4 Hz, anechoic
Hertz Recommended Sealed Volume	22.7 liters per driver
Driver Fs	24 Hz (S2) / 23 Hz (S4)
Driver Qts	0.51 (S2) / 0.42 (S4), S4 is the better damped on this size
Driver Qes / Qms	0.55 / 7.5 (S2) \| 0.45 / 6.3 (S4)
Driver Vas	64.9 L (S2) / 62.1 L (S4)
Driver BL	12.3 T·m (S2) / 18.7 T·m (S4)
Driver Mms	295 g (S2) / 320 g (S4)
Driver Xmax	16.8mm
Driver Sensitivity	84.5 dB (S2) / 85 dB (S4)
Driver Voice Coil	38mm, single voice coil
Driver Motor	High density flux ferrite
Suggested Filters	15 Hz subsonic at 24 dB/oct, 70 to 80 Hz low pass at 24 dB/oct (Hertz)
Power Handling	500 W RMS each / 1000 W RMS combined
Voice Coil Configuration	Single voice coil per driver; pair wired in parallel at the cup, 1 ohm (S2) or 2 ohm (S4)
Mounting Depth	3.465 in
Woofer Opening	11.14 in, both positions
Driver Frame Diameter	12.532 in, sits on the 14 in baffle
Driver Displacement	0.08 cu ft, estimated, no manufacturer figure
Material	Langboard Elite 3/4 in MDF
Joinery	V-groove and dado, CNC cut on ShopSabre routers
Panel Thickness	0.75 in
Front Baffle	1.5 in double baffle, outer layer machined as a flush recess
Internal Bracing	Full-height 3/4 in divider
Corner Profile	Square, Down Fire series standard
Driver Mounting	8/32 threaded inserts, stainless machine screws included
Terminal Cup	One Proline X ABS and carbon fiber composite, side mounted, pre-wired 12 gauge OFC to both driver positions
Damping	Polyfill installed as a light wall lining in both chambers, does not alter acoustic volume
Feet	1.75 in, included, shipped uninstalled
Carpet	Plush black
Bundle Options	Enclosure only, bring your own pair of MPS 300 S2 or S4
Warranty	1 year limited
Built In	Tullahoma, Tennessee

Performance Graphs

Net airspace

0.807

cu ft per chamber

System Qtc

0.81–1.00

sealed

Half power

37.0–39.4

Hz · F3

Xmax at

808

W RMS · no filter

With 25 Hz subsonic

889

W RMS · +10%

Amplifier

500

W RMS recommended

This enclosure holds 0.807 cu ft net per chamber. In it the Hertz Mille PRO MPS 300 S2 / S4 runs a system Qtc of 0.81–1.00 with half power at 37.0–39.4 Hz, and the cone reaches its 16.8 mm travel limit at 808 W, above the driver’s 500 W thermal rating, so heat stops you before travel does. Run a subsonic filter at 25 Hz and that becomes 889 W — +82 W, or 10 percent more power for the same 16.8 mm of travel.

01Is it a sealed driver?

Efficiency bandwidth product places the motor before anything else is decided.

EBP = Fs ÷ Qes = 43.6–51.1

S2 · EBP 43.6S4 · EBP 51.1

The Mille PRO MPS 300 straddles the boundary at 43.6–51.1 depending on coil — part sealed-band, part transition. Either way it takes a sealed load happily; the coil you run shifts the alignment more than it shifts this verdict.

02What the box does to it

0.807 cu ft against a 64.9 L Vas.

α = Vas ÷ Vb = 2.84 · Fc = Fs√(α+1) = 44–47 Hz · Qtc = 0.81–1.00

S2 · Qtc 1.00, Fc 47 Hz, F3 37.0 HzS4 · Qtc 0.81, Fc 44 Hz, F3 39.4 Hz

The box lifts resonance from 23.0–24.0 Hz free-air to 44–47 Hz and half power lands at 37.0–39.4 Hz, anechoic, before any cabin gain.

03The watts that reach Xmax (in this enclosure)

Travel scales with the square root of power, so there is one wattage that puts the cone exactly on 16.8 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.

P_Xmax = 808–837 W unfiltered → 889–990 W with a 25 Hz subsonic

S2 · 837 W, no filterS4 · 808 W, no filterS2 · 889 W with subsonic at 25 Hz, 24 dB/octS4 · 990 W with subsonic at 25 Hz, 24 dB/octXmax 16.8 mm one-way

Every trace touches the limit and no further, because each is drawn at the exact power that puts that coil on 16.8 mm. Unfiltered that is 808 W, reached first at 21 Hz. It sits above the 500 W the driver can take thermally, so the voice coil gives up before the suspension does. The dashed traces are the same driver behind a subsonic filter at 25 Hz, 24 dB/oct: stopping the cone wasting travel below the passband lets it take 889 W before hitting the same 16.8 mm. That is 10 percent more amplifier for the price of one filter setting.

Param	Value	Unit	Note
Fs	24.00 / 23.00	Hz	free-air resonance
Qts	0.510 / 0.420		S2 / S4
Vas	64.90 / 62.10	L	equivalent compliance
Sd	541.6	cm²	effective piston area
Xmax	16.8	mm	one-way linear travel
Pe	500	W	continuous RMS
SPL	84.0	dB	1 W / 1 m, derived from T/S

Driver parameters as published by Hertz Mille PRO technical sheet. Curves computed against this enclosure’s actual net airspace.

Materials

Material

Built From a Spec Sheet, Not a Sales Sheet

Every Proline X Performance Series enclosure is CNC-cut from Langboard Elite MDF, 3/4" (18mm) panels produced to published mill specifications. Most enclosure manufacturers source generic MDF without published data. We can tell you the internal bond rating, the modulus of elasticity, the modulus of rupture, and the face and edge screw holding strength for every panel in this enclosure, because we chose the material based on those numbers, not on price or availability.

Langboard Elite is produced in the United States. The specifications below are pulled directly from Langboard's published mill data and are verifiable. This is the same panel stock used in our full Proline X lineup.

Specifications

Langboard Elite MDF: Published Mill Data

Property	Value	Why It Matters
Panel Stock	Langboard Elite MDF	Named, verifiable panel source, not generic "high-density MDF"
Thickness	3/4" (18mm)	Industry standard for subwoofer enclosures; panels below this flex under pressure
Density	48.5 lbs/ft³	Higher density = less porosity, better screw retention, reduced resonance
Internal Bond	200 psi	Measures resistance to delamination under sustained internal pressure. The most enclosure-relevant spec on this sheet
Modulus of Rupture (MOR)	4,200 psi	Bending strength before the panel breaks, relevant for larger unsupported baffle spans
Modulus of Elasticity (MOE)	410,000 psi	Stiffness under load; higher MOE means less panel flex under bass pressure, less resonance
Face Screw Holding	325 lbs	How firmly the panel surface holds a screw; critical for baffle joint integrity over time
Edge Screw Holding	250 lbs	Panel edge retention, relevant for every joint that isn't face-to-face

Internal Bond

200 psi: The Number That Actually Matters for Enclosures

The internal bond rating measures how well the MDF panel resists delamination under sustained pressure applied perpendicular to the face. In a subwoofer enclosure, every bass transient generates a pressure pulse that pushes outward on every panel simultaneously. A panel that begins to delaminate internally loses stiffness gradually. The symptoms are slow: a box that starts to sound softer, less defined, less punchy over months of use. 200 psi internal bond is the spec that determines how long this enclosure holds its acoustic integrity under daily use at real power levels.

Stiffness

410,000 psi MOE: Less Flex, Less Resonance

The modulus of elasticity measures panel stiffness, its resistance to bending under load. A stiffer panel flexes less under the pressure generated by a high-excursion driver at volume. Panel flex is a source of acoustic coloration: the panel itself begins to radiate sound at its own resonant frequency, adding distortion to the output. 410,000 psi stiffness combined with V-groove and dado joinery means the panels stay rigid and the bracing controls resonance at the structure level, not the panel level. The bass you hear comes from the driver, not the box.

Screw Holding

325 lb Face / 250 lb Edge: Joints That Stay Locked

Screw holding strength determines how firmly the panel grips a fastener at the face and at the edge. This matters most at the baffle joint, where the front panel meets the side panels and where the driver is mounted. A panel with low screw holding strength allows fasteners to loosen over time under vibration, leading to air gaps at the joint and loss of acoustic seal. 325 lb face screw holding strength means the baffle hardware stays put. Combined with dado joinery and adhesive, the front panel on a Proline X Performance Series enclosure is not going anywhere.

Sourcing

Named Panel Stock: Not "Premium MDF"

The phrase "premium MDF" or "high-density MDF" appears on marketing copy for enclosures across every price point, from $40 to $400. It is not a specification. It is a description with no defined standard. Langboard Elite is a named, sourced, mill-documented product with published data. We name it in our copy because naming it holds us accountable to the spec. You can look up Langboard Elite independently, verify the numbers on this page, and confirm you are getting what we say you are getting. That is the point.

Why Proline X?

Most enclosures are built to a price point. Proline X is built to a spec. Every box starts with published-data MDF, gets CNC-cut to exact internal volume, and is assembled by hand in our Tennessee facility. The difference shows up in the measurements, and in how the box holds up two years into daily use.

CNC-Cut to Spec

Panels are machine-cut on ShopSabre CNC routers and joined with V-groove and dado joinery. Consistent geometry, no hand-cut variance, no gaps at the joints.