JL Audio W7 Owner's Manual page 11

Driver Specifications
Grille clearance: 2.25 in. (57 mm) from the bottom of the mounting
flange to the lowest inside surface of the grille.
Displacement: 0.09 cu. ft. (2.5 ltrs)
Net Weight: 30 lbs. (15.8 kg)
Mounting
Hole
Diameter
8.74 in.
(222 mm)
Magnet
Diameter
6.55 in.
(166 mm)
Enclosure Specifications
Net volumes given below do not include the air volume displaced by
the speaker (Driver Displacement). This value must be added to the
net volume along with the displacement of any braces and/or ports (if
applicable) to arrive at a gross internal volume. Air inside a port is not part
of the effective net volume. Calculate ports as solid, not hollow objects.
The dimensions given for the enclosure examples below take all applicable
displacements into consideration.
External Depth
15 in.
(381 mm)
External Height
14 in.
(356 mm)
External Width
15.5 in.
(394 mm)
SEALED ENcLOSURE:
Recommended Net Volume: 1.25 cu. ft. (35.4 ltrs.)
fc: 44.7 Hz f3: 40.7 Hz Qtc: 0.785
front Baffle Thickness: 1 in. (25 mm)
Wall Thickness: 0.75 in. (19 mm)
Mounting Hardware: Twelve #10 x 1.75" long clear, zinc-plated steel
Phillips pan-head sheet metal screws (included) or twelve #10-32 long
steel Phillips pan-head machine screws with #10-32 T-Nuts, each at
least 1/2-inch (12.5 mm) longer than the thickness of the mounting
baffle (not included).
Unpacking/Mounting: Please refer to the "How to: Mount a W7
Subwoofer " on pages 4 & 5 for detailed, step-by-step instructions.
Bolt Hole
Circle
9.34 in.
(237 mm)
12 Holes
Overall
Diameter
10.5 in.
(267 mm)
SAfETY NOTIcE!
It is absolutely essential that the completed subwoofer enclosure is mounted
firmly to the vehicle with heavy steel bolts (1/2 inch diameter) and large steel
washers on both sides of the bolts. This will reduce the likelihood of occupant
injury in the event of a collision or sudden deceleration.
External Depth
14.5 in.
(368 mm)
External Height
Slot Height
13.5 in.
12.0 in.
(343 mm)
(305 mm)
External Width
23.375 in.
(594 mm)
PORTED ENcLOSURE:
Recommended Net Volume: 1.5 cu. ft. (42.5 ltrs.)
Recommended Port Tuning: 32 Hz
Port Type: "Slot" ports are recommended. See information above.
The port recommendations listed above are derived through actual
tests and measurements (not computer simulations).
front Baffle Thickness: 1 in. (25 mm)
Wall Thickness: 0.75 in. (19 mm)
Mounting
Depth
8 in.
(203 mm)
Slot Length
22.5 in.
(572 mm)
Slot Width
1.5 in.
(38 mm)
Extension Length
7.25 in.
(184 mm)
Slot Width
1.5 in.
(38 mm)
Overall
Depth
9.63 in.
(245 mm)
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