Performance Optimized · Datasheet

Performance Optimized Down Fire Ported 10" Enclosure | Rockford Fosgate P3SD4-10 Single 10" Ported enclosure

Net volume
1.27 Cubic Feet
Tuning
35.0 Hz
Max mounting depth
3.500 Inches (Rockford Fosgate Spec)
Cutout
9.060 Inches (Rockford Fosgate Spec)
External dimensions
31 Inches W × 7.75 Inches H × 15.50 Inches D
Front baffle
Down Firing - Driver Fires Toward Floor
Buy at Audio Intensity
  • Alignment: 1.27 cu ft net vented at 35.0 Hz. F3 29.2 Hz anechoic, 2.59 dB passband ripple
  • Driver: Rockford Fosgate P3SD4-10 D4, 300 W RMS, 8.1 mm Xmax, 42.00 Hz Fs
  • Build: Proline X V-groove and dado joinery, L-wrap slot port with a faceted 90 degree bend, double-layer 1.5" baffle, side-mounted terminal cup
  • Cabinet: 31" W x 15.50" D x 7.75" H measured in down fire position, 9.50" tall installed on its feet, square corners, ships dry

Technical specifications

SeriesProline X Performance Optimized Down Fire
Driver-Specific FitmentRockford Fosgate P3SD4-10 D4 (Dual 4 Ohm)
Enclosure TypePorted | Down Fire Geometry | Floor-Coupled
Baffle ConfigurationDown Firing - Driver Fires Toward Floor
External Width31 Inches
External Depth15.50 Inches
External Height7.75 Inches (Cabinet Only)
FeetIncluded - 1.75 Inch Standoff, Required For Down Fire Operation
Installed Height9.50 Inches (7.75 Cabinet Plus 1.75 Feet) - MEASURE AGAINST THIS, NOT THE CABINET HEIGHT
Dimension ReferenceAll External Dimensions Measured In Down Fire Position
Internal Volume (Gross)1.44 Cubic Feet
Internal Volume (Net After Displacement)1.27 Cubic Feet
Port TypeL-Wrap Slot | One Folded Wall | Single Faceted 90 Degree Bend
Port Tuning (Fb)35.0 Hz
Port Channel3.25 x 6.25 Inches (20.3 Square Inches)
Port Path Length27.69 Inches (Centreline)
Port Mouth Area22.1 Square Inches (2.50 Inch Corner Chamfer)
Port Air Velocity13.9 m/s At Tuning (17.0 m/s Chuff Threshold)
Predicted F329.2 Hz (Anechoic)
Passband Ripple2.59 dB (Anechoic)
Subsonic Filter28 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure
Driver Fs42.00 Hz
Driver Qts0.780
Driver Qes / Qms0.900 / 6.000
Driver Vas14.300 Liters / 0.505 Cubic Feet
Driver Sd333.0 Square Centimeters
Driver Re6.8 Ohm
Driver Xmax8mm (One-Way)
Driver Displacement0.07 Cubic Feet (Published by Rockford Fosgate)
Driver Sensitivity83.0 dB
Driver Power Handling300 Watts RMS
Driver Overall Diameter11.020 Inches (Rockford Fosgate Spec)
Mounting Depth Required3.500 Inches (Rockford Fosgate Spec)
Cutout Diameter9.060 Inches (Rockford Fosgate Spec)
Woofer Ring12.000 Inch OD, Bonded Under The Baffle In A Machined Recess
MaterialLangboard Elite 3/4" MDF
ConstructionShopSabre CNC / Windowed Brace Between Cutout And Port Terminus
JoineryV-Groove and Dado (CNC-Cut)
Front Baffle ConstructionDouble-Layer 1.5" MDF | Outer Layer Flush Recess, Driver Mounts To Inner Layer
Corner ProfileSquare (Down Fire Series Standard)
Mounting Hardware8 x #8-32 Hurricane Nuts Fitted (16 Positions Cut For Driver Orientation) | Stainless Steel Machine Screws Included
Voice Coil ConfigurationDual 4 Ohm
Terminal CupProline X ABS/Carbon Fiber Composite | Side Mounted | 12g OFC Pre-Wired
DampingNone - Ships Dry. Polyfill Detunes A Ported Enclosure
Recommended Power210-300 Watts RMS (Rockford Fosgate Rated: 300W RMS)
Carpet FinishPlush Black
Bundle OptionsEnclosure Only (Bring Your Own Rockford Fosgate P3SD4-10)
Warranty1-Year Limited (Enclosure)
ManufacturedTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
1.27
cu ft
Tuning
35.0
Hz · Fb
Half power
29.2
Hz · F3, anechoic
Xmax at
370
W RMS · 28 Hz subsonic
With NO filter
122
W RMS · unfiltered
Port
13.9
m/s at the mouth

01Is this driver right for a ported box?

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

EBP = Fs ÷ Qes = 46.7
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 EBP 46.7
Rockford Fosgate P3SD4-10 · EBP 46.7
Under 50 the raw number leans sealed. The Rockford Fosgate P3SD4-10 reads 46.7, so this is a ported build against the grain of its own EBP: it works because the alignment is tuned for in-car response rather than for an anechoic curve, and because the cabinet holds port area and volume the driver can actually use.

02What the box does to it

1.27 cu ft net against a 14.3 L Vas, vented at 35.0 Hz.

Fb = 35.0 Hz  ·  F3 = 29.2 Hz  ·  passband ripple 2.59 dB
20 30 50 70 100 150 200 +6 +0 −6 −12 −18 −24 FREQUENCY · Hz LEVEL · dB −3 dB Fb 35.0
Rockford Fosgate P3SD4-10 · Fb 35.0 Hz, F3 29.2 Hz
Anechoic, before any cabin gain, with the 28 Hz subsonic filter already applied. The vent takes over below 35 Hz and the cone stops doing the work there, which is what holds travel down at the bottom of the passband.

03Perceived Ported vs Sealed

This cabinet, 1.27 cu ft net vented at 35.0 Hz, against the 0.92 cu ft sealed Down Fire we build for this driver (PO 10-S DF P3S).

Ported Fb 35.0 Hz  ·  the 0.92 cu ft sealed box runs Qtc 0.97, Fc 52 Hz
20 30 50 70 100 150 200 +6 +0 −6 −12 −18 −24 FREQUENCY · Hz LEVEL · dB +7.5 dB at 32 Hz
Ported · this cabinet, 1.27 cu ft, Fb 35.0 HzSealed Down Fire we build, 0.92 cu ft, Qtc 0.97
Shaded blue is where the ported alignment is louder for the same power, orange where the sealed one is. The sealed curve is the 0.92 cu ft sealed Down Fire we build for this driver (PO 10-S DF P3S), not this cabinet with the port blocked: two different boxes, because that is the choice a buyer actually has. Across 25 to 60 Hz the vent is worth 7.5 dB at its widest and 5.4 dB on average. This is the anechoic picture, which is not what you hear in a car.

04Real World Ported vs Sealed

The same two boxes with cabin gain applied, 45 Hz corner, 18 dB ceiling.

Flatness across 25–60 Hz: ported 4.0 dB spread, the 0.92 cu ft sealed box 2.5 dB
20 30 50 70 100 150 200 +6 +0 −6 −12 −18 −24 FREQUENCY · Hz LEVEL · dB +7.5 dB at 32 Hz
Ported, in-car · 4.0 dB spreadSealed Down Fire we build, 0.92 cu ft, in-car · 2.5 dB spread
Cabin gain lifts both boxes by the same amount, so the gap between them does not change: what changes is the shape each one ends up with. A car pressurises below roughly 45 Hz, which fills in the sealed box's shallower rolloff and over-drives it where the ported box is already flat. Across 25 to 60 Hz, the band kick and bass fundamentals occupy, this alignment holds 4.0 dB of spread against 2.5 dB for the 0.92 cu ft sealed Down Fire we build for this driver (PO 10-S DF P3S). The sealed curve is flatter on paper; the ported one trades that for output. Note where the curves cross. Below about 22 Hz the sealed alignment becomes the louder of the two and stays louder all the way down, by up to 2.3 dB: a sealed box rolls off gently into the subsonic region where a vented one falls away steeply once it is below tuning and the vent stops contributing. If the content you are chasing lives below 22 Hz, a sealed alignment reaches further down than this one does. Cabin gain here is a house assumption, not a measurement of your vehicle.

05The 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 Rockford Fosgate's published 8.1 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.

PXmax = 370 W with a 28 Hz subsonic  ·  122 W with none  →  the filter is worth 3.0×
20 30 50 70 100 150 200 0 4 8 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 8.1 mm 370 W reaches Xmax here
370 W · subsonic at 28 Hz, 24 dB/oct122 W · no subsonic filterXmax 8.1 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 8.1 mm. With a 28 Hz subsonic that takes 370 W, reached first at 27 Hz. Take the filter away and the same cabinet reaches 8.1 mm on 122 W — the filter is worth 3.0× 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 122 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 — Rockford Fosgate rate this one at 300 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 300 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.

Installer's take

3.50 inches and 300 watts. The shallow tens in this programme usually make you pick one or the other, and the closest comparison, the IDQS10, is the same depth for 200 watts.

The F3 is the surprise: 29.2 Hz anechoic, deeper than the full-depth P1 and P2 tens from the same brand. That is not the driver, which resonates at 42 Hz with only 14.3 litres of Vas. It is the box doing work the motor cannot.

The cost lands in the car. 3.9 dB of in-car spread against the R2 Shallow's 2.3, at nearly the same mounting depth. A 42 Hz motor has stopped contributing before cabin gain shows up, and there is no alignment that fixes it.

So the choice between the two shallow Rockford tens is real: this one for watts, the R2 Shallow for curve. I would not tell you which without knowing what you are running.

Dual 4 ohm: 2 ohms parallel or 8 ohms series. Subsonic at 28 Hz. Ships dry.

Questions

Why is this enclosure tuned to 35.0 Hz?

1.27 cubic feet vented at 35.0 Hz reaches an anechoic F3 of 29.2 Hz, which is deeper than the full-depth P1 and P2 tens in the same brand manage. A 42 Hz resonance with 14.3 litres of Vas is a stiff motor, and the alignment leans on the box rather than the driver to get down there. Tuning is chosen for in-car response rather than for an anechoic curve: a vehicle adds roughly 12 dB per octave below about 45 Hz, so a box tuned very low reinforces a region the cabin is already reinforcing and leaves 40 to 60 Hz thin. In this cabinet that lands at 4.0 dB of in-car spread across 25 to 60 Hz, which is where kick and bass fundamentals live.

Does this enclosure ship with polyfill?

No, and on this build in particular do not add any. Every sealed Proline X enclosure ships with polyfill pre-installed; a ported one must not, because damping material changes the effective volume the port is tuned against. The port on this cabinet is cut to 27.69 inches of centreline path for 35.0 Hz. Stuff it and you move the tuning without shortening the port, which gives you a mistuned box rather than a bigger-sounding one. The 2.59 dB passband you are paying for depends on it staying dry.

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 Rockford Fosgate P3SD4-10 at 90 percent of its usable travel at full rated power; without it there is no meaningful number to quote, because the excursion curve does not converge. On a sealed build a subsonic filter is an improvement. Here it is required equipment.

How much power can I run?

Rockford Fosgate rate the P3SD4-10 at 300 W RMS and that is the thermal ceiling. The figures on the Performance Graphs tab are a different quantity: they are mechanical limits, the power at which the cone reaches the end of its linear travel in this specific cabinet. Here the cone sits at 90 percent of usable travel at the driver's own rating, so heat is what stops you, not travel. Final wired impedance and amplifier output are separate questions again.

Would a sealed box be better for me?

Below about 22 Hz, yes. The sealed Down Fire we build for it is louder down there by up to 2.3 dB, because a sealed box rolls off gently into the subsonic region where a vented one falls away steeply once it is under tuning. Above that this alignment is the louder of the two for the same power. The Performance Graphs tab plots this cabinet, 1.27 cubic feet vented at 35.0 Hz, against the 0.92 cu ft sealed Down Fire we build for this driver (PO 10-S DF P3S), so you can see exactly where they cross.

What is the L-wrap port and why does it matter?

It is a slot port formed by one folded wall: a leg down the long side of the cabinet past the woofer ring, one faceted 90 degree bend, and a leg across the end opening through a chamfered corner. On this cabinet that is 27.69 inches of centreline path and 20.3 square inches of channel, exiting a 22.1 square inch mouth. Air leaves at 13.9 metres per second at tuning against a 17.0 threshold, and the channel runs at 40 percent of its turbulence limit. One wall and one bend rather than a serpentine's three means less wall area inside the box, fewer joints to leak, and one place for flow to separate instead of three.

How is this enclosure built?

V-groove and dado joinery in 0.75 inch Langboard Elite MDF with a double-layer 1.5 inch baffle. The driver mounts to a 12.000 inch ring bonded under the baffle in a machined recess, carrying eight #8-32 hurricane nuts so it threads into steel rather than MDF. A windowed brace sits 3.38 inches clear of the cutout edge and 1.91 inches clear of the port terminus; the window is not weight saving, a solid panel there would split the cavity and make the box a bandpass. Walls seat into dados in both the lid and the baffle. Square corners, plush black carpet, side-mounted terminal cup.

Is the P3SD4-10 included?

No. This is an enclosure only, cut and folded for the Rockford Fosgate P3SD4-10 specifically. The 9.060 inch cutout, the 3.500 inch mounting depth allowance and the 1.27 cubic foot alignment all come from Rockford Fosgate's published parameters for this exact driver, and the port is sized against its Xmax and power rating. It is not a universal box with a 10 inch hole in it. Bring your own driver.

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