
Performance Optimized · Datasheet
Performance Optimized Wedge Ported 8" Enclosure | Prodigy NB2-8 Single 8" Ported enclosure
- Net volume
- 0.93 Cubic Feet
- Tuning
- 35.0 Hz
- Max mounting depth
- 5.000 Inches (Prodigy Spec)
- Cutout
- 7.188 Inches (Prodigy Spec)
- External dimensions
- 29.00 Inches W × 11.75 Inches H × 8.88 Inches / 13.15 Inches D
- Front baffle
- Vertical Baffle - Driver Fires Rearward Into The Trunk
- Alignment: 0.93 cu ft net vented at 35.0 Hz. F3 29.3 Hz anechoic, 4.44 dB passband ripple
- Driver: Prodigy NB2-8 D4, 300 W RMS, 14.0 mm Xmax, 37.34 Hz Fs
- Build: Rear-firing wedge, 20 degree rear rake, V-groove and dado joinery, triangular side-exit slot port with a 1/2" rounded mouth, double 1.5" baffle, side-mounted terminal cup
- Cabinet: 29.00" W x 11.75" H x 13.15" D at base tapering to 8.88" D at top, 13.0 sq in port, ships dry
Technical specifications
| Series | Proline X Performance Optimized Wedge |
|---|---|
| Driver-Specific Fitment | Prodigy NB2-8 D4 (Dual 4 Ohm) |
| Enclosure Type | Ported | Rear-Firing Trunk Wedge |
| Baffle Configuration | Vertical Baffle - Driver Fires Rearward Into The Trunk |
| Wedge Angle | 20 Degrees On The Rear (Seat-Side) Panel |
| External Width | 29.00 Inches |
| External Height | 11.75 Inches |
| Top Depth | 8.88 Inches |
| Base Depth | 13.15 Inches |
| Internal Volume (Gross) | 1.26 Cubic Feet |
| Internal Volume (Net After Displacement) | 0.93 Cubic Feet |
| Port Type | Triangular Slot | Bottom-Rear Corner | Straight, No Bend | Side Exit |
| Port Geometry | Isosceles, 5.25 Inch Legs, 13.0 Square Inches, 24.53 Inches Long, Side Mouth |
| Port Tuning (Fb) | 35.0 Hz |
| Port Mouth | Triangle Through Side A, 1/2 In Roundover On All Three Edges, 22.5 Square Inches At The Face |
| Port Throat | Open Far End, 2.72 In Gap To Side B, 3/8 In Roundover On The Panel End |
| Port Air Velocity | 21.6 m/s In The Channel, 12.4 m/s At The Flared Mouth (17.0 m/s Chuff Threshold) |
| Predicted F3 | 29.3 Hz (Anechoic) |
| Passband Ripple | 4.44 dB (Anechoic) |
| Subsonic Filter | 28 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 37.34 Hz |
| Driver Qts | 0.448 |
| Driver Qes / Qms | 0.515 / 3.417 |
| Driver Vas | 6.955 Liters / 0.246 Cubic Feet |
| Driver Sd | 202.9 Square Centimeters |
| Driver Mms | 117.44 g |
| Driver BL | 17.88 |
| Driver Re | 6.1 Ohm |
| Driver Xmax | 14mm (One-Way at 70% BL) |
| Excursion Design Basis | Derated To 11.9mm For Alignment - Prodigy Publishes At 70% BL |
| Driver Displacement | 0.07 Cubic Feet (Published by Prodigy) |
| Driver Sensitivity | 83.7 dB |
| Driver Power Handling | 300 Watts RMS |
| Driver Overall Diameter | 8.500 Inches (Prodigy Spec) |
| Mounting Depth Required | 5.000 Inches (Prodigy Spec) |
| Cutout Diameter | 7.188 Inches (Prodigy Spec) |
| Material | Langboard Elite 3/4" MDF |
| Construction | ShopSabre CNC / Two Windowed C Braces At The Third Points, Seated On The Port Panel |
| Joinery | V-Groove and Dado (CNC-Cut) |
| Front Baffle Construction | Double-Layer 1.5" MDF | Cosmetic Front Layer Routed For The Acrylic Insert |
| Mounting Hardware | Threaded Inserts At Every Mounting Location | Stainless Steel Machine Screws Included |
| Voice Coil Configuration | Dual 4 Ohm |
| Terminal Cup | Proline X ABS/Carbon Fiber Composite | Side Mounted, Opposite The Port | 12g OFC Pre-Wired |
| Damping | None - Ships Dry. Polyfill Detunes A Ported Enclosure |
| Recommended Power | 210-300 Watts RMS (Prodigy Rated: 300W RMS) |
| Carpet Finish | Plush Black |
| Weight | 41 lb |
| Bundle Options | Enclosure Only (Bring Your Own Prodigy NB2-8) |
| Warranty | 1-Year Limited (Enclosure) |
| Manufactured | Tullahoma, Tennessee, USA |
Performance in this enclosure
01Is this driver right for a ported box?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
0.93 cu ft net against a 7.0 L Vas, vented at 35.0 Hz.
03Ported vs Sealed
No sealed comparison is shown for this driver.
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 14.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
Installer's take
An eight with a 0.45 Qts and 7 litres of Vas will go low in a box this size, and the NB2-8 does: 29.3 Hz anechoic at 35 Hz tuning. What it will not do is stay flat in the car. 8.70 dB of spread across 25 to 60 Hz is the second widest figure in the ported wedge line, because a 37 Hz motor with this much reach gets the cabin's rise stacked on a bottom end that is already full. The NB2-10 in this line reads 3.92 dB; if the install has room for a ten, that is the better Prodigy.
The channel runs 21.6 metres per second at 300 watts against the 20.9 limit the rest of the line holds. I built it anyway, on the judgment that 0.7 metres per second at rated power is inside the noise of the model, and it is disclosed here so nobody finds it later. Xmax is quoted at 70 percent BL and derated from 14 to 11.9 mm; the cone uses 7.7 of that at 300 watts with the subsonic filter set. Run the filter.
Questions
Why is this enclosure tuned to 35.0 Hz?
A low Qts eight on 7 litres reaches far below its resonance in this much air, F3 29.3 Hz anechoic on 4.44 dB of ripple, and that reach costs flatness in the car: 8.70 dB of spread across 25 to 60 Hz, the second widest in the ported wedge line. The port takes 24.53 of the 24.88 inches available and runs at 21.6 metres per second in the channel at 300 watts, over the 20.9 limit the line normally holds by 0.7; that figure was reviewed and accepted for this cabinet. 12.4 at the rounded mouth. Tuning is chosen for in-car response rather than an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz. In this cabinet that lands at 8.5 dB of in-car spread across 25 to 60 Hz.
Why the 20 degree wedge, and why rear-firing?
The raked face is the seat side. A factory rear seat back leans about 20 degrees off vertical, so the cabinet sits flat against it and uses floor a square box wastes. The baffle stays vertical and fires rearward into the trunk, which acts as the acoustic extension into the cabin. This one is 13.15 inches deep at the base and 8.88 at the top, 29.00 wide and 12 tall.
Do I need a subsonic filter?
Yes, at 28 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 Prodigy NB2-8 at 65 percent of its usable travel at full rated power; without it there is no meaningful number to quote.
How much power can I run, and at what impedance?
Prodigy rate the NB2-8 at 300 W RMS and that is the thermal ceiling. The Performance Graphs tab shows the mechanical limit, the power at which the cone reaches the end of its travel in this cabinet: here the cone sits at 65 percent of usable travel at the rating, so heat is what stops you, not travel. A D2 coil is 4 ohms in series or 1 ohm in parallel; run series unless the amplifier is rated for 1 ohm. A D4 is 8 series or 2 parallel.
Would a sealed box be better for me?
Not one we can show you. We do not build a sealed enclosure for the Prodigy NB2-8 and Prodigy 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 28 Hz subsonic filter takes over; around 35.0 Hz the vent carries the load and cone travel drops to its minimum, which no sealed alignment can do.
How does the side port work?
It is a triangular slot in the bottom-rear corner: the floor and the raked back wall are two sides, one bevelled panel is the third. It runs across the cabinet, opens into the box through a 2.72 inch gap at the far end and exits through the side panel as the same triangle. Straight, no bend: 24.53 inches of path and 13.0 square inches of channel running at 21.6 metres per second, 57 percent of its turbulence limit. The three mouth edges are rounded over at 1/2 inch, so the opening at the face is 22.5 square inches and the air leaves it at 12.4 metres per second against the 17.0 threshold where a slot port starts to chuff; the panel's throat end is rounded at 3/8 inch for the same reason. The terminal cup is on the other side.
Does this enclosure ship with polyfill?
No, and do not add any. Every sealed Proline X enclosure ships with polyfill; a ported one must not, because damping changes the effective volume the port is tuned against. The port here is cut to 24.53 inches for 35.0 Hz. Stuff it and you move the tuning without shortening the port.
Is the NB2-8 included?
No. This is an enclosure only, cut for the Prodigy NB2-8 specifically: the 7.188 inch cutout, the 5.000 inch mounting depth allowance and the 0.93 cubic foot alignment all come from Prodigy's published parameters. It fits both coil versions; the alignment published here is the D4. Bring your own driver.
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