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Proline X
Professional Series Ported 15" Enclosure | Prodigy Audio NB5-15
SKU: Pro15-P NB5 NA D2
QUICK SPECS
- Alignment: 3.00 cu ft net vented at 33.0 Hz
- Driver: Prodigy NB5-15 D2, 1200 W RMS, 27.0 mm Xmax, 35.60 Hz Fs
- Build: Front-firing standard box, triple 2.25" baffle with the woofer flush-mounted in the outer layer, Prodigy logo acrylic, dado joinery, 48.0 sq in slot port beside the woofer, internally braced
- Cabinet: 32.00" W x 17.50" H x 19.00" D, 85 lb
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.
$ 1,199.99
Financing available. Choose Shop Pay Installments at checkout.
Professional Series Ported 15" Enclosure | Prodigy Audio NB5-15
Enclosure Type
Ported
External Dimensions
32.00" W x 17.50" H x 19.00" D
Gross Volume
4.52 cu ft
Net Volume
3.00 cu ft
Tuning Frequency
33.0 Hz
Port Area
48.0 Square Inches
Shipping Weight
92 lbs
INSTALLER'S TAKE
Product Details
Enclosure Specifications
Performance Graphs
Woofer Details
Materials
Professional Series Ported 15" Enclosure | Prodigy Audio NB5-15
A ported fifteen-inch box built to Prodigy's own published numbers for the NB5-15, bare or loaded
3.00 cu ft net
Tuned 33.0 Hz
Triple 2.25" baffle
Cut for the Prodigy NB5-15
Built in Tennessee
Why this driver is vented at 33.0 Hz
The Prodigy NB5-15 pairs a deep motor with a wide frame, and this cabinet gives it 3.00 cubic feet net, vented at 33.0 Hz through a 48.0 square inch port. F3 lands at 28.6 Hz with 1.55 dB of passband ripple. It is the largest single-driver box in the professional line, and it ships bare with a choice of baffle finish or loaded with the driver already mounted.
The port on this box stays clean up to 851 W before the mouth velocity crosses the chuff threshold, against the coil's own 1200 W power rating. Prodigy publish Xmax on a 70 percent BL basis for this driver, and the excursion check behind this build derates that figure further rather than taking the spec sheet number at face value. Ripple across the passband holds at 1.55 dB, and the in-car curve stays tight across the passband rather than peaking at either end.
The cabinet
32.00" W x 17.50" H x 19.00" D external, internally braced. It ships as a UPS parcel; the price includes shipping in the 48 states.
This is our largest single-driver ported envelope in the professional line, sold bare with a choice of baffle finish or loaded with the NB5-15 already mounted in either coil.
The numbers to respect
T/S for the NB5-15 D2 are Prodigy's own published figures; the D4 version of this coil also fits this cabinet. There are no dimension or tuning conflicts between the Q2 catalog sheet and the store listing on this cabinet.
This cabinet is 3.00 cubic feet net, with a slot port of 48.0 square inches tuned to 33.0 Hz; the port stays under the chuff threshold up to 851 W; above that the air at the mouth moves faster than the 17 metres per second where a slot starts to chuff.
Set a 26 Hz subsonic filter, 24 dB per octave. Below tuning the vent stops loading the cone; with the filter in place the cone reaches 10.8 mm of its 22.9 mm at 1800 W.
| Series | Proline X Professional |
| Driver-Specific Fitment | Prodigy NB5-15 D2 (Dual 2 Ohm) |
| Enclosure Type | Ported | Front-Firing Standard Box |
| External Width | 32.00 Inches |
| External Height | 17.50 Inches |
| External Depth | 19.00 Inches |
| Internal Volume (Net) | 3.00 Cubic Feet |
| Port Type | Vertical Slot Beside The Woofer | Front Exit | Internally Braced |
| Port Area | 48.0 Square Inches |
| Port Tuning (Fb) | 33.0 Hz |
| Design Power Basis | 1800 W RMS (1.5 x The Driver Rating) |
| Driver Fs | 35.60 Hz |
| Driver Qts | 0.485 |
| Driver Qes / Qms | 0.534 / 5.283 |
| Driver Vas | 43.548 Liters / 1.538 Cubic Feet |
| Driver Sd | 858.4 Square Centimeters |
| Driver Mms | 422.32 g |
| Driver BL | 27.33 |
| Driver Re | 3.4 Ohm |
| Driver Xmax | 27mm (One-Way) |
| Driver Power Handling | 1200 Watts RMS |
| Driver Overall Diameter | 16.125 Inches (Prodigy Spec) |
| Mounting Depth Required | 9.750 Inches (Prodigy Spec) |
| Cutout Diameter | 13.750 Inches (Prodigy Spec) |
| Flush Mount Recess | 17.125 Inches In The Outer Layer |
| Voice Coil Configuration | Dual 2 Ohm |
| Material | Langboard Elite 3/4" MDF |
| Joinery | Dado Joinery (CNC-Cut), Flat Panels |
| Front Baffle Construction | Triple-Layer 2.25" MDF | Woofer Flush-Mounted In The Outer Layer |
| Baffle Layers | 3 |
| Acrylic | Glossy Black Prodigy Logo Insert, Outer Layer, Standard |
| 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 |
| Carpet Finish | Plush Black |
| Shipping Weight | 92 lb |
| Shipping | UPS Ground Parcel, Included In The 48 States |
| Bundle Options | Enclosure Only (Bring Your Own Prodigy NB5-15) |
| Warranty | 2-Year Limited (Enclosure) |
| Manufactured | Tullahoma, Tennessee, USA |
Net airspace
3.00
cu ft
Tuning
33.0
Hz · Fb
Half power
28.6
Hz · F3, anechoic
Xmax at
11325
W RMS · 26 Hz subsonic
With NO filter
2925
W RMS · unfiltered
Port
24.7
m/s at the mouth · 1800 W
01Is this driver right for a ported box?
Efficiency bandwidth product places the motor before anything else is decided.
EBP = Fs ÷ Qes = 66.7
Prodigy NB5-15 D2 · EBP 66.7
Between 50 and 100 a driver takes either load, and the choice becomes one of priorities rather than of physics. The Prodigy NB5-15 D2 reads 66.7. 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
3.00 cu ft net against a 43.5 L Vas, vented at 33.0 Hz.
Fb = 33.0 Hz · F3 = 28.6 Hz · passband ripple 1.55 dB
Prodigy NB5-15 D2 · Fb 33.0 Hz, F3 28.6 Hz
Anechoic, before any cabin gain, with the 26 Hz subsonic filter already applied. The vent takes over below 33 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 Prodigy NB5-15 D2 — we do not build a sealed enclosure for it and Prodigy 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 the cone exactly on Prodigy's published 27.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
PXmax = 11325 W with a 26 Hz subsonic · 2925 W with none → the filter is worth 3.9×
11325 W · subsonic at 26 Hz, 24 dB/oct2925 W · no subsonic filterXmax 27.0 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 27.0 mm. With a 26 Hz subsonic that takes 11325 W, reached first at 26 Hz. Take the filter away and the same cabinet reaches 27.0 mm on 2925 W — the filter is worth 3.9× 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 2925 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 — Prodigy rate this one at 1200 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 1200 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. The dashed line at 22.9 mm is the figure the cabinet was actually designed against: Prodigy publish this Xmax on a 70% BL basis, and we derate it before sizing the port so the alignment carries margin against an optimistic spec rather than sitting right on it.
The Prodigy Audio NB5-15 is the driver this enclosure was built around, a 15" subwoofer engineered from the motor out for high-output daily use without the compromises that typically come with drivers in this power class. With 27mm of one-way Xmax at 70% BL, 1200 watts RMS power handling, and a BL factor of 27.33 Tm on the D2 variant, the NB5-15 produces the kind of sustained high-output bass that its 280-ounce ferrite motor and 2.75" flat aluminum voice coil were designed to deliver. Its Qts of 0.485–0.536 places it at the ported alignment threshold, and in a correctly sized ported enclosure at 33Hz it produces deep, controlled bass output with the headroom to handle real-world power levels without thermal or mechanical compromise. Prodigy Audio also designed the NB5-15 with serviceability in mind, the motor incorporates vented pole design with coil gap radial vents that move heat out of the gap quickly, keeping the voice coil cooler during sustained high-power use. Full driver specifications are available at prodigyaudio.com.
| Brand / Model | Prodigy Audio NB5-15 |
| Size | 15" |
| Impedance Options | Dual 2-ohm (D2) / Dual 4-ohm (D4) |
| RMS Power | 1200W |
| Xmax (one-way at 70% BL) | 27mm |
| BL Factor (D2) | 27.33 Tm |
| BL Factor (D4) | 30.789 Tm |
| Fs (D2) | 35.6Hz |
| Fs (D4) | 34.93Hz |
| Qts (D2) | 0.485 |
| Qts (D4) | 0.536 |
| Vas (D2) | 43.548L |
| Vas (D4) | 47.197L |
| Sensitivity (D2) | 88.22 dB (1W/1m) |
| Sensitivity (D4) | 88.965 dB (1W/1m) |
| Voice Coil | 2.75" flat aluminum |
| Motor | 280 oz ferrite | vented pole | coil gap radial vents |
| Cone | Competition grade treated paper |
| Dust Cap | Carbon fiber |
| Surround | Heavy-duty foam |
| Spider | Nomex with stitched tinsel leads |
| Frame | Heavy-duty cast aluminum |
| Cutout Diameter | 13.75" |
| Overall Diameter | 16.125" |
| Mounting Depth | 9.75" |
| Driver Weight | 45 lbs |
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.
Handcrafted in USA
Hand-assembled at our facility in Tullahoma, TN. Every enclosure is inspected before it ships.
Tuned to the Build
Internal volume and port geometry are calculated to spec and CNC-cut to exact dimensions. The box performs the same way every time.
Shop By Series
Economy Series
Value Driven - Standard Output
Performance Series
High Output - Universal Ported & Sealed
Performance Optimized Series
Precision Tuned - Brand Specific Geometry
Performance Wedge Series
Angled Back - Truck & Hatchback Ready
Professional Series
Competition Grade - Double Baffle High SPL
Micro Series
Compact Sealed - Small Footprint Efficiency
Down Fire Series
Under Seat - Cargo Safe Down-Firing
Vehicle Specific Series
OEM Fitment - Stealth Truck & SUV Solutions
Loaded Series
Plug & Play - Subwoofer + Box Bundles
