Performance Optimized Down Fire Sealed 10" Enclosure Sony XS-W104ES · Single 10" Sealed enclosure

The XS-W104ES, yes. The baffle is cut to 9.21 in (234 mm), Sony's published cutout, under the 279 mm (10.98 in) frame. Some dealer listings quote 9-1/16 in; that is 4 mm short of Sony's figure. The 5.39 inch motor clears the cabinet with 0.75 inch to spare, and Sony sells the XS-W104ES in one version, a single 4 ohm coil, so there is no variant to choose.

Any other 10, no. The airspace is engineered around the XS-W104ES's 0.49 Qts and 23.3 liters of Vas, and a different woofer that happened to drop into the hole would not see the alignment printed on this page.

Because the XS-W104ES's 5.39 inch mounting depth sets the minimum cabinet height on the 30 by 15 platform, not the target volume. The motor reaches 3.89 inches into the cavity and needs 0.75 inch above it, which puts the cabinet at 6.89 inches tall and the airspace at 0.91 cubic feet whether the alignment wants it or not.

The result is a slightly over-damped alignment, Qtc 0.677, resonance 54.7 Hz, half power 57.3 Hz: a gentle rolloff rather than a flat one, and still tighter than Sony's own 1.01 cubic foot box at Qtc 0.66. The wedge and the dual down fire, where the motor does not bind, hold the 0.76 Butterworth volume.

Sony rates the XS-W104ES at 450 watts RMS to CTA-2031 and 1800 watts short-term maximum, so target 315 to 450 watts RMS at the final load.

The XS-W104ES has a single 4 ohm voice coil (3.8 ohms DC), so one driver presents 4 ohms to a mono amplifier. Confirm your amplifier's minimum stable impedance first.

The cabinet is 6.89 inches tall measured in the down fire position, and that figure excludes the standoffs. The standoffs hold 1.75 inches under the baffle, so plan your space around a finished stack of roughly 8.64 inches.

The footprint is the standard Performance Optimized down fire platform, 30.00 inches wide by 15.00 deep. Height is the only dimension solved to the driver, and here it is the XS-W104ES's 5.39 inch motor that sets it.

The baffle is two bonded 3/4 inch sheets, 1.5 inches through. A single 3/4 inch panel flexes under the pressure a 10 inch woofer puts on it at 450 watts, which smears output and works the driver loose over time; the second layer stiffens the face and gives the mounting hardware twice the material to bite.

The outer layer is machined as a flush recess to Sony's 10.98 inch frame, so the driver bolts to the inner layer.

Anechoic F3 is 57.3 Hz with system resonance at 54.7 Hz. Below Qtc 0.707 the rolloff is gentle and F3 sits above fc, which is what an over-damped sealed box does.

Those figures exclude cabin gain. In a car the cabin's transfer function adds real output below 50 Hz, so in-vehicle response runs deeper than the numbers above.

No. Polyfill is already installed as a light wall lining to control internal reflections, and the quantity is chosen so it does not change the acoustic volume.

Do not add more. Packing a sealed box with fill makes it behave as though it were larger, which walks the alignment away from the 0.91 cubic feet this cabinet was built to.

No driver. This is an enclosure only. You receive the cabinet finished in plush black carpet, one side-mounted pre-wired terminal cup, the polyfill lining already in place, the standoffs, and a threaded insert kit with stainless machine screws.

The inserts ship loose on purpose: Sony prints no bolt circle for the XS-W104ES, so you set the driver in the recess, mark its holes, drill and press the inserts. The Sony XS-W104ES is purchased separately, and the cabinet is cut direct fit to it, not a general purpose 10 inch box.