
Performance Optimized · Datasheet
Performance Optimized Down Fire Ported 10" Enclosure | Image Dynamics IDQ10 V4 Single 10" Ported enclosure
- Net volume
- 1.44 Cubic Feet
- Tuning
- 35.5 Hz
- Max mounting depth
- 5.807 Inches (Image Dynamics Spec)
- Cutout
- 9.570 Inches (Image Dynamics Spec)
- External dimensions
- 31 Inches W × 7.75 Inches H × 17.50 Inches D
- Front baffle
- Down Firing - Driver Fires Toward Floor
- Alignment: 1.44 cu ft net vented at 35.5 Hz. F3 33.3 Hz anechoic, 2.37 dB passband ripple
- Driver: Image Dynamics IDQ10 V4, 250 W RMS, 14.5 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 17.50" D x 7.75" H measured in down fire position, 9.50" tall installed on its feet, square corners, ships dry
Technical specifications
| Series | Proline X Performance Optimized Down Fire |
|---|---|
| Driver-Specific Fitment | Image Dynamics IDQ10 V4 |
| Enclosure Type | Ported | Down Fire Geometry | Floor-Coupled |
| Baffle Configuration | Down Firing - Driver Fires Toward Floor |
| External Width | 31 Inches |
| External Depth | 17.50 Inches |
| External Height | 7.75 Inches (Cabinet Only) |
| Feet | Included - 1.75 Inch Standoff, Required For Down Fire Operation |
| Installed Height | 9.50 Inches (7.75 Cabinet Plus 1.75 Feet) - MEASURE AGAINST THIS, NOT THE CABINET HEIGHT |
| Dimension Reference | All External Dimensions Measured In Down Fire Position |
| Internal Volume (Gross) | 1.65 Cubic Feet |
| Internal Volume (Net After Displacement) | 1.44 Cubic Feet |
| Port Type | L-Wrap Slot | One Folded Wall | Single Faceted 90 Degree Bend |
| Port Tuning (Fb) | 35.5 Hz |
| Port Channel | 4.00 x 6.25 Inches (25.0 Square Inches) |
| Port Path Length | 29.01 Inches (Centreline) |
| Port Mouth Area | 22.1 Square Inches (2.50 Inch Corner Chamfer) |
| Port Air Velocity | 12.2 m/s At Tuning (17.0 m/s Chuff Threshold) |
| Predicted F3 | 33.3 Hz (Anechoic) |
| Passband Ripple | 2.37 dB (Anechoic) |
| Subsonic Filter | 28 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 42.00 Hz |
| Driver Qts | 0.797 |
| Driver Qes | 0.992 |
| Driver Vas | 24.300 Liters / 0.858 Cubic Feet |
| Driver Sd | 380.1 Square Centimeters |
| Driver Xmax | 14mm (One-Way) |
| Driver Displacement | 0.10 Cubic Feet (Published by Image Dynamics) |
| Driver Power Handling | 250 Watts RMS |
| Driver Overall Diameter | 11.040 Inches (Image Dynamics Spec) |
| Mounting Depth Required | 5.807 Inches (Image Dynamics Spec) |
| Cutout Diameter | 9.570 Inches (Image Dynamics Spec) |
| Woofer Ring | 12.000 Inch OD, Bonded Under The Baffle In A Machined Recess |
| Material | Langboard Elite 3/4" MDF |
| Construction | ShopSabre CNC / Windowed Brace Between Cutout And Port Terminus |
| Joinery | V-Groove and Dado (CNC-Cut) |
| Front Baffle Construction | Double-Layer 1.5" MDF | Outer Layer Flush Recess, Driver Mounts To Inner Layer |
| Corner Profile | Square (Down Fire Series Standard) |
| Mounting Hardware | 8 x #8-32 Hurricane Nuts Fitted (16 Positions Cut For Driver Orientation) | Stainless Steel Machine Screws Included |
| Terminal Cup | Proline X ABS/Carbon Fiber Composite | Side Mounted | 12g OFC Pre-Wired |
| Damping | None - Ships Dry. Polyfill Detunes A Ported Enclosure |
| Recommended Power | 175-250 Watts RMS (Image Dynamics Rated: 250W RMS) |
| Carpet Finish | Plush Black |
| Bundle Options | Enclosure Only (Bring Your Own Image Dynamics IDQ10 V4) |
| 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
1.44 cu ft net against a 24.3 L Vas, vented at 35.5 Hz.
03Perceived Ported vs Sealed
This cabinet, 1.44 cu ft net vented at 35.5 Hz, against the 1.00 cu ft sealed wedge we build for this driver (PO 10-S W IDQ BB).
04Real World Ported vs Sealed
The same two boxes with cabin gain applied, 45 Hz corner, 18 dB ceiling.
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 IDQ10's published 14.5 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
Installer's take
Two numbers on this driver point away from a vent. Fs 42.0 and Qts 0.797, giving an EBP of 42.3. I built it ported anyway and I will tell you why.
A port has to be sized for the work it is asked to do, and 250 watts through a 24.3 litre Vas is not much work. That means the vent can be generous relative to the demand, and generous is where ports stop being audible. The channel runs at 28 percent of its turbulence limit, the lowest loadingin this entire range, and the mouth sees 12.2 metres per second against a17 threshold. This is the box I would put in a car where the owner will notice port noise.
In-car it lands at 2.0 dB of spread across 25 to 60 Hz, which is a genuinely flat result and better than three of the twelves here. High Qts is not a problem when the box is sized for it; it is a problem when it is not.
Where it does not compete is depth. 42 Hz free-air is a hard floor and no alignment argues with it. The ten-inch NB2 in this same line reaches 29.9 Hz against this one's 33.3. If low is the priority, buy that one.
250 W RMS and it does not want more. Subsonic at 28 Hz. No polyfill, and at this port velocity you will never have a reason to wonder about it.
Questions
Why is this enclosure tuned to 35.5 Hz?
The result is the least loaded port we build: a 25.0 square inch channelrunning at 28 percent of its turbulence limit, the lowest figure in therange, with 12.2 metres per second at the mouth against a 17 threshold. There is no condition in normal use where this port makes a sound of its own. Tuned to 35.5 Hz it reaches an F3 of 33.3 Hz with 2.0 dB of in-car spread. 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 1.9 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 29.01 inches of centreline path for 35.5 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 2.37 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 Image Dynamics IDQ10 V4 at 48 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?
Image Dynamics rate the IDQ10 V4 at 250 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 48 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?
The two alignments converge at the bottom of the band on this driver rather than crossing cleanly, so there is no meaningful subsonic advantage either way. Above 25 Hz the vent is the louder of the two for the same power. The Performance Graphs tab plots this cabinet, 1.44 cubic feet vented at 35.5 Hz, against the 1.00 cu ft sealed wedge we build for this driver (PO 10-S W IDQ BB), so you can judge it yourself.
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 29.01 inches of centreline path and 25.0 square inches of channel, exiting a 22.1 square inch mouth. Air leaves at 12.2 metres per second at tuning against a 17.0 threshold, and the channel runs at 28 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 3.39 inches clear of the cutout edge and 2.17 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 IDQ10 V4 included?
No. This is an enclosure only, cut and folded for the Image Dynamics IDQ10 V4 specifically. The 9.570 inch cutout, the 5.807 inch mounting depth allowance and the 1.44 cubic foot alignment all come from Image Dynamics'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.
Other Performance Optimized models
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- Arc Audio SW10 Dual 10" Sealed
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