Performance Optimized · Datasheet

Performance Optimized Down Fire Ported 10" Enclosure | Image Dynamics IDQS10 Single 10" Ported enclosure

Net volume
1.43 Cubic Feet
Tuning
34.5 Hz
Max mounting depth
3.504 Inches (Image Dynamics Spec)
Cutout
9.567 Inches (Image Dynamics Spec)
External dimensions
31 Inches W × 7.75 Inches H × 16.50 Inches D
Front baffle
Down Firing - Driver Fires Toward Floor
Buy at Audio Intensity
  • Alignment: 1.43 cu ft net vented at 34.5 Hz. F3 29.7 Hz anechoic, 2.47 dB passband ripple
  • Driver: Image Dynamics IDQS10 D4, 200 W RMS, 7.5 mm Xmax, 50.00 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 16.50" 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 FitmentImage Dynamics IDQS10 D4 (Dual 4 Ohm)
Enclosure TypePorted | Down Fire Geometry | Floor-Coupled
Baffle ConfigurationDown Firing - Driver Fires Toward Floor
External Width31 Inches
External Depth16.50 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)1.55 Cubic Feet
Internal Volume (Net After Displacement)1.43 Cubic Feet
Port TypeL-Wrap Slot | One Folded Wall | Single Faceted 90 Degree Bend
Port Tuning (Fb)34.5 Hz
Port Channel3.75 x 6.25 Inches (23.4 Square Inches)
Port Path Length29.14 Inches (Centreline)
Port Mouth Area30.9 Square Inches (3.50 Inch Corner Chamfer)
Port Air Velocity9.0 m/s At Tuning (17.0 m/s Chuff Threshold)
Predicted F329.7 Hz (Anechoic)
Passband Ripple2.47 dB (Anechoic)
Subsonic Filter27 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure
Driver Fs50.00 Hz
Driver Qts1.020
Driver Qes / Qms1.220 / 6.230
Driver Vas14.263 Liters / 0.504 Cubic Feet
Driver Sd391.0 Square Centimeters
Driver Mms160.00 g
Driver BL17.60
Driver Re7.6 Ohm
Driver Xmax8mm (One-Way)
Driver Displacement0.00 Cubic Feet (Published by Image Dynamics)
Driver Sensitivity84.7 dB
Driver Power Handling200 Watts RMS
Driver Overall Diameter11.024 Inches (Image Dynamics Spec)
Mounting Depth Required3.504 Inches (Image Dynamics Spec)
Cutout Diameter9.567 Inches (Image Dynamics 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 Power140-200 Watts RMS (Image Dynamics Rated: 200W RMS)
Carpet FinishPlush Black
Bundle OptionsEnclosure Only (Bring Your Own Image Dynamics IDQS10)
Warranty1-Year Limited (Enclosure)
ManufacturedTullahoma, Tennessee, USA

Performance in this enclosure

Net airspace
1.43
cu ft
Tuning
34.5
Hz · Fb
Half power
29.7
Hz · F3, anechoic
Xmax at
316
W RMS · 27 Hz subsonic
With NO filter
150
W RMS · unfiltered
Port
9.0
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 = 41.0
SEALED 0–50 TRANSITION 50–100 PORTED 100–150 0 50 100 150 EBP 41.0
Image Dynamics IDQS10 D4 · EBP 41.0
Under 50 the raw number leans sealed. The Image Dynamics IDQS10 D4 reads 41.0, 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

1.43 cu ft net against a 14.3 L Vas, vented at 34.5 Hz.

Fb = 34.5 Hz  ·  F3 = 29.7 Hz  ·  passband ripple 2.47 dB
20 30 50 70 100 150 200 +6 +0 −6 −12 −18 −24 FREQUENCY · Hz LEVEL · dB −3 dB Fb 34.5
Image Dynamics IDQS10 D4 · Fb 34.5 Hz, F3 29.7 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 Image Dynamics IDQS10 D4 — we do not build a sealed enclosure for it and Image Dynamics 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 Image Dynamics's published 7.5 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.

PXmax = 316 W with a 27 Hz subsonic  ·  150 W with none  →  the filter is worth 2.1×
20 30 50 70 100 150 200 0 4 8 FREQUENCY · Hz CONE TRAVEL · mm PAST LINEAR TRAVEL · Xmax 7.5 mm 316 W reaches Xmax here
316 W · subsonic at 27 Hz, 24 dB/oct150 W · no subsonic filterXmax 7.5 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 7.5 mm. With a 27 Hz subsonic that takes 316 W, reached first at 27 Hz. Take the filter away and the same cabinet reaches 7.5 mm on 150 W — the filter is worth 2.1× 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 150 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 — Image Dynamics rate this one at 200 W RMS, and that is the number that binds first here: heat stops you before travel does, so treat 200 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

A 50 Hz free-air resonance with a 1.02 Qts is, on paper, a driver with no low end worth talking about. Put it in 1.43 cubic feet vented at 34.5 Hz and it reaches 29.7 Hz anechoic, deeper than any twelve inch Image Dynamics driver in this programme, the IDQ12 and the ID12 included.

That is the alignment doing the work rather than the motor, and it is the strongest argument I can make for solving a box per driver instead of selling a universal one. Nothing about this driver suggests 29.7 Hz. The enclosure produces it.

3.504 inches of mounting depth is why anyone buys it. Same basket as the IDQ10, but the shallow series does not share the IDQ's depth: 5.807 against 3.504. If you have seen those conflated, catch it before you cut a hole.

Travel is the limit. 7.5 mm one-way, half of what the full-depth drivers here carry, and it will stop you before the 200 watt rating does on anything with real bottom end. In-car spread is 4.4 dB, which is well down the field, so buy it for the depth it fits into rather than for flatness. Subsonic at 27 Hz, not optional.

Frame OD and bolt circle come from Image Dynamics' own cutout template, the only place either is published for this series. D4 coil, 2 ohms parallel or 8 ohms series.

Questions

Why is this enclosure tuned to 34.5 Hz?

It works because the alignment is doing what the motor cannot. A 50 Hz free-air resonance and a 1.02 Qts describe a driver with no natural low end at all, and 1.43 cubic feet vented at 34.5 Hz builds one. The port is 23.4 square inches running at 33 percent of its turbulence limit, so nothing is being forced to get 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 4.3 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 29.14 inches of centreline path for 34.5 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 2.47 dB passband you are paying for depends on it staying dry.

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 Image Dynamics IDQS10 at 79 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 IDQS10 at 200 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 79 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?

Not one we can show you. We do not build a sealed enclosure for the Image Dynamics IDQS10 and Image Dynamics 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.

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 29.14 inches of centreline path and 23.4 square inches of channel, exiting a 30.9 square inch mouth. Air leaves at 9.0 metres per second at tuning against a 17.0 threshold, and the channel runs at 33 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 2.85 inches clear of the cutout edge and 1.63 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 IDQS10 included?

No. This is an enclosure only, cut and folded for the Image Dynamics IDQS10 specifically. The 9.567 inch cutout, the 3.504 inch mounting depth allowance and the 1.43 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