
Performance Optimized · Datasheet
Performance Optimized Wedge Ported 8" Enclosure | Image Dynamics IDQS8 Single 8" Ported enclosure
- Net volume
- 0.78 Cubic Feet
- Tuning
- 34.0 Hz
- Max mounting depth
- 3.110 Inches (Image Dynamics Spec)
- Cutout
- 7.299 Inches (Image Dynamics Spec)
- External dimensions
- 30.00 Inches W × 11.75 Inches H × 7.25 Inches / 11.53 Inches D
- Front baffle
- Vertical Baffle - Driver Fires Rearward Into The Trunk
- Alignment: 0.78 cu ft net vented at 34.0 Hz. F3 29.4 Hz anechoic, 1.83 dB passband ripple
- Driver: Image Dynamics IDQS8 D2, 125 W RMS, 7.0 mm Xmax, 53.00 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: 30.00" W x 11.75" H x 11.53" D at base tapering to 7.25" D at top, 10.6 sq in port, ships dry
Technical specifications
| Series | Proline X Performance Optimized Wedge |
|---|---|
| Driver-Specific Fitment | Image Dynamics IDQS8 D2 (Dual 2 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 | 30.00 Inches |
| External Height | 11.75 Inches |
| Top Depth | 7.25 Inches |
| Base Depth | 11.53 Inches |
| Internal Volume (Gross) | 1.04 Cubic Feet |
| Internal Volume (Net After Displacement) | 0.78 Cubic Feet |
| Port Type | Triangular Slot | Bottom-Rear Corner | Straight, No Bend | Side Exit |
| Port Geometry | Isosceles, 4.75 Inch Legs, 10.6 Square Inches, 25.66 Inches Long, Side Mouth |
| Port Tuning (Fb) | 34.0 Hz |
| Port Mouth | Triangle Through Side A, 1/2 In Roundover On All Three Edges, 19.4 Square Inches At The Face |
| Port Throat | Open Far End, 2.59 In Gap To Side B, 3/8 In Roundover On The Panel End |
| Port Air Velocity | 14.3 m/s In The Channel, 7.8 m/s At The Flared Mouth (17.0 m/s Chuff Threshold) |
| Predicted F3 | 29.4 Hz (Anechoic) |
| Passband Ripple | 1.83 dB (Anechoic) |
| Subsonic Filter | 27 Hz High-Pass, 24 dB/Octave - REQUIRED On A Vented Enclosure |
| Driver Fs | 53.00 Hz |
| Driver Qts | 0.980 |
| Driver Qes / Qms | 1.350 / 3.610 |
| Driver Vas | 6.418 Liters / 0.227 Cubic Feet |
| Driver Sd | 214.0 Square Centimeters |
| Driver Mms | 92.00 g |
| Driver BL | 10.20 |
| Driver Re | 4.6 Ohm |
| Driver Xmax | 7mm (One-Way) |
| Driver Displacement | 0.03 Cubic Feet (Published by Image Dynamics) |
| Driver Sensitivity | 81.8 dB |
| Driver Power Handling | 125 Watts RMS |
| Driver Overall Diameter | 8.346 Inches (Image Dynamics Spec) |
| Mounting Depth Required | 3.110 Inches (Image Dynamics Spec) |
| Cutout Diameter | 7.299 Inches (Image Dynamics 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 2 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 | 87-125 Watts RMS (Image Dynamics Rated: 125W RMS) |
| Carpet Finish | Plush Black |
| Weight | 40 lb |
| Bundle Options | Enclosure Only (Bring Your Own Image Dynamics IDQS8) |
| 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
0.78 cu ft net against a 6.4 L Vas, vented at 34.0 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 Image Dynamics's published 7.0 mm. The two traces are the same cabinet with the subsonic filter switched on and switched off.
Installer's take
The IDQS8 is a 53 Hz motor with a Qts near 1 on 3.11 inches of mounting depth. Sealed, that is a peaky alignment with no reach; vented at 34 Hz in 0.78 cubic feet the port supplies the bottom octave and the F3 lands at 29.4 Hz on 1.83 dB of ripple. In the car it spreads 5.40 dB across 25 to 60 Hz, because the driver itself is gone before cabin gain arrives. The IDQS10 in this line is the same family with a little more of everything.
7 mm of one-way travel is the whole story on power. The cone uses 5.3 of it at 125 watts with the subsonic filter set, and on material with real bottom end the suspension arrives before the rating does. Set the filter, keep the gain honest. The port is one of the quietest in the line, 14.3 metres per second in the channel and 7.8 at the mouth, so port noise is not a concern here; excursion is.
Questions
Why is this enclosure tuned to 34.0 Hz?
A high Qts shallow eight has no reach of its own; the port supplies it. At 34 Hz the anechoic F3 is 29.4 Hz on 1.83 dB of ripple, and in the car it spreads 5.40 dB across 25 to 60 Hz, because a 53 Hz motor is gone before cabin gain arrives. The port takes 25.66 of the 26.11 inches available and runs at 14.3 metres per second in the channel against a 14.9 limit, 7.8 at the rounded mouth, one of the quietest ports in the line. 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 5.2 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 11.53 inches deep at the base and 7.25 at the top, 30.00 wide and 12 tall.
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 IDQS8 at 76 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?
Image Dynamics rate the IDQS8 at 125 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 76 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 Image Dynamics IDQS8 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 34.0 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 2.59 inch gap at the far end and exits through the side panel as the same triangle. Straight, no bend: 25.66 inches of path and 10.6 square inches of channel running at 14.3 metres per second, 52 percent of its turbulence limit. The three mouth edges are rounded over at 1/2 inch, so the opening at the face is 19.4 square inches and the air leaves it at 7.8 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 25.66 inches for 34.0 Hz. Stuff it and you move the tuning without shortening the port.
Is the IDQS8 included?
No. This is an enclosure only, cut for the Image Dynamics IDQS8 specifically: the 7.299 inch cutout, the 3.110 inch mounting depth allowance and the 0.78 cubic foot alignment all come from Image Dynamics's published parameters. It fits both coil versions; the alignment published here is the D2. Bring your own driver.
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