Proline X

Professional Series Ported Dual 8" Enclosure | NVX NSW8v3

Q: Do I need a subsonic filter?

Yes, at 27 Hz, 24 dB per octave. Below tuning a vented box stops loading the cone and excursion runs away toward DC. With the filter in place this cabinet puts the NVX NSW8v3 at 79 percent of its usable travel at 960 W.

Q: Would a sealed box be better for me?

Not one we can show you. We do not build a sealed enclosure for the NVX NSW8v3 and NVX publish no sealed volume for it, so the Performance Graphs tab carries no ported-versus-sealed chart: the only sealed box left to plot would be this cabinet stuffed and sealed, which nobody would build, and a comparison against it would tell you nothing you could buy. What a vented box gives up is the region below tuning, where the cone unloads and the 27 Hz subsonic filter takes over; around 34.5 Hz the vent carries the load and cone travel drops to its minimum, which no sealed alignment can do.

Q: How does the front port work?

It is a vertical slot beside the woofer, the full height of the cavity, 2.25 inches wide and 28.1 square inches. It runs 6.75 inches to the back wall and turns once along it for 21.79 inches; the fold costs about 1.5 Hz and the port is cut for it. The channel runs at 23.1 metres per second at 960 W, 51 percent of its turbulence limit, and the mouth edges carry a 1/2 inch roundover so the air leaves the face at 14.8 metres per second against the 17 metres per second threshold where a slot starts to chuff.

Q: What does the price cover, and how does it ship?

52 lb, 34.00" W x 14.00" H x 12.75" D external. Every Professional cabinet is priced the same way, by its size: this one is 3.51 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 52 lb parcel and checkout adds nothing. Do not add polyfill; it ships dry on purpose.

Q: Is the NSW8v3 included?

No. This is an enclosure only, cut for the NVX NSW8v3 specifically: the 7.120 inch cutout, the 4.980 inch mounting depth allowance and the 1.46 cubic foot alignment all come from NVX's published parameters. It fits both coil versions (D2 and D4), and the cabinet was checked against both. Bring your own driver.

SKU: Pro 8D-P NSW

QUICK SPECS

Alignment: 1.46 cu ft net vented at 34.5 Hz. F3 29.5 Hz anechoic, 3.30 dB passband ripple
Driver: NVX NSW8v3 D2/D4, 400 W RMS, 10.5 mm Xmax, 39.10 Hz Fs
Build: Front-firing standard box, 2.25" three-layer baffle with the woofer flush-mounted in the outer layer, NVX logo acrylic, dado joinery, 28.1 sq in front slot port beside the woofer with one bend along the back wall, port and excursion gated at 960 W
Cabinet: 34.00" W x 14.00" H x 12.75" D, 52 lb, threaded inserts pressed into the baffle on the published 7.790 inch bolt circle

Shipping Included No freight charges at checkout on US orders. International orders are quoted live carrier rates at checkout.

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.

$ 441.99

In Stock and Ready to Ship

Financing available. Choose Shop Pay Installments at checkout.

Complete Your System

Image Dynamics Image Dynamics SQ600.1D 600W Mono Block Amplifier $ 399.99

Professional Series Ported Dual 8" Enclosure | NVX NSW8v3

$ 441.99

More enclosures cut for NVX subwoofers: NVX Subwoofer Boxes

Enclosure Type Ported

External Dimensions 34.00" W x 14.00" H x 12.75" D

Gross Volume 2.22 cu ft

Net Volume 1.46 cu ft

Tuning Frequency 34.5 Hz

Port Area 28.1 Square Inches

Shipping Weight 59 lbs

INSTALLER'S TAKE

I built this one for a pair of NSW8v3 in a single shared chamber, which is how a dual ported box should be built: one volume, one port, both drivers loading the same air.

It gets the full Professional treatment, a 2.25 inch three-layer baffle with both woofers flush mounted in the outer layer, and the port on the left of the face.

Wiring is where a dual bites you. These are two 2 ohm coils each, so you can land on 0.5 ohm with all four coils in parallel, 2 ohms as two series pairs in parallel, or 8 ohms with everything in series. Check what your amplifier is rated for before you wire it, not after.

It ships dry. Do not add polyfill to a ported box. Set your subsonic filter at 27 Hz.

Product Details

Proline X Professional 8" Ported

A ported eight inch box for a pair of NSW8v3, one shared chamber vented at 34.5 Hz

1.46 cu ft net Tuned 34.5 Hz F3 29.5 Hz 2.25" three-layer baffle Cut for the NSW8v3 Built in Tennessee

1.46cu ft net

34.5Hz tuning

29.5Hz F3 anechoic

28.1sq in port area

Why this driver is vented at 34.5 Hz

This cabinet holds two NSW8v3 in 1.464 cubic feet net, vented at 34.5 Hz through a 28.1 square inch port. F3 lands at 29.5 Hz with 3.30 dB of passband ripple. It measures 34.00 inches wide, 14.00 tall and 12.75 deep.

Both drivers share one chamber and one port rather than sitting in separate boxes, so the pair works against the whole volume and the port is sized for the pair rather than doubled. The port carries 28.1 square inches of area at 34.5 Hz, and the design power for the velocity and excursion checks is 960 W for the pair. Passband ripple holds at 3.30 dB across the tuning, with F3 at 29.5 Hz.

What makes it Professional

Three-layer baffle, flush mount

Three layers of 3/4 inch Langboard Elite make a 2.25 inch front. The outer layer is routed to the flange, so the woofer sits flush with the face; the two layers behind it carry the mounting hardware and the load.

NVX logo acrylic

A glossy black acrylic insert with the NVX mark sits in the outer layer beside the woofer. It is standard on every Professional cabinet.

Mounting

Threaded inserts pressed into the baffle on the published 7.790 inch bolt circle, stainless machine screws included.

Port gated at 960 W

The 28.1 square inch slot beside the woofer is sized so the channel runs 23.1 metres per second and the mouth 14.8 metres per second at 1.2 times the driver's rating, under the 17 metres per second where a slot starts to chuff. The channel runs 6.75 inches along its wall and turns once along the back wall for another 21.79 inches, which is why a 34.5 Hz tuning fits a 12.75 inch deep box.

Why this is a Professional build

A single NSW8v3 also builds in the Performance Optimized ported down-fire, the smaller and cheaper single-driver box. A pair takes this Professional cabinet: one shared chamber on a 2.25 inch three-layer baffle with both woofers flush in the outer layer, and a slot port gated at 960 W for the pair.

What the price covers

Every Professional cabinet is priced the same way, by its size: this one is 3.51 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 52 lb parcel and checkout adds nothing.

The cabinet

34.00" W x 14.00" H x 12.75" D external. A windowed brace runs front to back beside the woofer, clearing the cutout by two and a half inches. The box ships dry: polyfill detunes a ported alignment. This is our dual 8 inch Professional envelope, built around the NSW8v3's own frame and mounting depth, with both woofers on one face and the port on the left. It ships as a parcel.

Port mouth velocity peaks at 14.8 m/s against the 17 m/s point where a slot begins to chuff, and 23.1 m/s in the channel, both measured at the pair's design power. Both drivers must be the same model and the same coil: mixing them puts unequal loads on one shared chamber, and neither driver sees the airspace it was picked for.

The numbers to respect

Set a 27 Hz subsonic filter, 24 dB per octave. Below tuning the vent stops loading the cone; with the filter in place the cone reaches 8.3 mm of its 10.5 mm at 960 W.

Enclosure Specifications

Series	Proline X Professional
Driver-Specific Fitment	NVX NSW8v3 D2/D4 (Dual 2 Ohm or Dual 4 Ohm)
Enclosure Type	Ported \| Front-Firing Standard Box
External Width	34.00 Inches
External Height	14.00 Inches
External Depth	12.75 Inches
Internal Volume (Gross)	2.22 Cubic Feet
Internal Volume (Net After Displacement)	1.46 Cubic Feet
Port Type	Vertical Slot Beside The Woofer \| Front Exit \| One 90 Degree Bend Along The Back Wall
Port Geometry	2.25 x 12.50 Inches, 28.1 Square Inches, 34.54 Inches Of Path
Port Area	28.1 Square Inches
Port Tuning (Fb)	34.5 Hz
Port Mouth	1/2 In Roundover On All Four Edges, 43.9 Square Inches At The Face
Port Air Velocity	23.1 m/s In The Channel, 14.8 m/s At The Mouth, At 960 W (17.0 m/s Chuff Threshold)
Design Power Basis	960 W RMS (1.2 x The Driver Rating) For Port Velocity And Excursion
Predicted F3	29.5 Hz (Anechoic)
Passband Ripple	3.30 dB (Anechoic)
Subsonic Filter	27 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure
Driver Fs	39.10 Hz
Driver Qts	0.385
Driver Qes / Qms	0.421 / 4.521
Driver Vas	6.050 Liters / 0.214 Cubic Feet
Driver Sd	201.0 Square Centimeters
Driver Re	3.8 Ohm
Driver Xmax	10mm (One-Way)
Driver Displacement	0.03 Cubic Feet (Published by NVX)
Driver Sensitivity	85.0 dB
Driver Power Handling	400 Watts RMS
Driver Overall Diameter	8.460 Inches (NVX Spec)
Mounting Depth Required	4.980 Inches (NVX Spec)
Cutout Diameter	7.120 Inches (NVX Spec)
Flush Mount Recess	9.375 Inches In The Outer Layer
Material	Langboard Elite 3/4" MDF
Construction	ShopSabre CNC / Windowed Brace Front To Back Beside The Woofer
Joinery	Dado Joinery (CNC-Cut), Flat Panels
Front Baffle Construction	Three 3/4" MDF layers, 2.25" total \| Woofer Flush-Mounted In The Outer Layer
Baffle Layers	3
Acrylic	Glossy Black NVX Logo Insert, Outer Layer, Standard
Mounting Hardware	Threaded Inserts On The Published 7.790 In Bolt Circle \| Stainless Machine Screws Included
Voice Coil Configuration	Dual 2 Ohm
Terminal Cup	Proline X ABS/Carbon Fiber Composite \| Back Panel, Terminal-Cup Side \| 12g OFC Pre-Wired
Damping	None - Ships Dry. Polyfill Detunes A Ported Enclosure
Recommended Power	280-400 Watts RMS (NVX Rated: 400W RMS)
Carpet Finish	Plush Black
Shipping Weight	59 lb
Shipping	UPS Ground Parcel, Included In The 48 States
Bundle Options	Enclosure Only (Bring Your Own NVX NSW8v3)
Warranty	2-Year Limited (Enclosure)
Manufactured	Tullahoma, Tennessee, USA

Performance Graphs

Net airspace

1.46

cu ft

Tuning

34.5

Hz · Fb

Half power

29.5

Hz · F3, anechoic

Xmax at

1525

W RMS · 27 Hz subsonic

With NO filter

458

W RMS · unfiltered

Port

14.8

m/s at the mouth · 960 W

01Is this driver right for a ported box?

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

EBP = Fs ÷ Qes = 92.9

NVX NSW82v3 D2 · EBP 92.9

Between 50 and 100 a driver takes either load, and the choice becomes one of priorities rather than of physics. The NVX NSW82v3 D2 reads 92.9. Ported buys output and low-end reach around tuning; sealed buys a shallower rolloff below it. This cabinet takes the first trade.

02What the box does to it

1.46 cu ft net against a 12.1 L Vas, vented at 34.5 Hz.

Fb = 34.5 Hz · F3 = 29.5 Hz · passband ripple 3.30 dB

NVX NSW82v3 D2 · Fb 34.5 Hz, F3 29.5 Hz

Anechoic, before any cabin gain, with the 27 Hz subsonic filter already applied. The vent takes over below 34 Hz and the cone stops doing the work there, which is what holds travel down at the bottom of the passband.

03Ported vs Sealed

No sealed comparison is shown for this driver.

A ported-versus-sealed chart is only worth reading against a sealed box someone would actually build: the one we make for the driver, or the one its maker recommends. Neither exists for the NVX NSW82v3 D2 — we do not build a sealed enclosure for it and NVX publish no sealed volume for it — so rather than compare this cabinet against itself stuffed and sealed, a box no one would build, the comparison is left out.

04The watts that reach Xmax (in this enclosure)

Travel scales with the square root of power, so there is one wattage that puts both cones exactly on NVX's published 10.5 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off. Every power figure in this section is for the pair, split evenly.

P_Xmax = 1525 W with a 27 Hz subsonic · 458 W with none → the filter is worth 3.3×

1525 W · subsonic at 27 Hz, 24 dB/oct458 W · no subsonic filterXmax 10.5 mm one-way, published

Each trace touches the limit and no further, because each is drawn at the exact power that puts the cone on 10.5 mm. With a 27 Hz subsonic that takes 1525 W, reached first at 28 Hz. Take the filter away and the same cabinet reaches 10.5 mm on 458 W — the filter is worth 3.3× the safe power. A vent unloads the cone below tuning, so there is nothing holding it once the box stops loading: on a sealed build a subsonic filter is an improvement, here it is required equipment. The unfiltered trace is still rising where this chart stops at 20 Hz, so treat 458 W as a bound rather than a floor. Every wattage on this page is a MECHANICAL limit, not an electrical one. It is the power at which the cone runs out of linear travel in this cabinet, and nothing more. What the voice coil can dissipate as heat is a separate ceiling set by the driver, not by the box — NVX rate this one at 800 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 800 W as the ceiling and the travel figures above as headroom. Final wired impedance, amplifier output and how long you hold the level are all electrical questions this graph does not answer.

Woofer Details

The NSW8v3 is the 8 inch in NVX's N-Series v3: an enhanced pressed paper cone on a high-roll foam surround, a 2.0 in voice coil, and a 90 oz double stacked ferrite magnet motor, rated 400 W RMS by NVX. NVX publishes the full Thiele-Small table, the displacement and the bolt circle for it in its owner's manual. This cabinet takes two of them in one shared chamber, so both drivers see the same air and the same port. Each opening is cut for 4.98 in of mounting depth and a 7.12 in cutout, taken from NVX's published figures rather than measured off a sample. Where a rating below carries no reference condition, that is because the maker does not state one, and it is left as they print it.

Driver	NVX NSW8v3
Coil Options	Dual 2 Ohm or Dual 4 Ohm
Voice Coil Diameter	2.0 in
Coil Former	Aluminum Former
Coil Wire	High Temperature Copper
Cone	Enhanced Pressed Paper Cone
Surround	High-Roll Foam Surround
Spider	Progressive Roll Single-layer Spider
Lead Wires	Integrated Tinsel Leads
Basket	Stamped Steel Vented Basket with NVX Punched Logo
Motor	90 oz. Double Stacked Ferrite Magnet with Protective Rubber boot
Cooling	Optimized High-Velocity Pole Vent
Power, RMS	400 W
Power, Peak	800 W
Sensitivity	85 dB, reference condition not stated by NVX
Mounting Depth	4.98 in
Cutout Diameter	7.12 in
Frame Outside Diameter	8.46 in
Driver Displacement	0.030 cu ft

Materials

Material

Built From a Spec Sheet, Not a Sales Sheet

Every Proline X Professional 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 Professional 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.