Performance Optimized Wedge Wide Sealed Dual 12" Enclosure Image Dynamics IDMAX12 V.4 · Dual 12" Sealed enclosure

Yes, both coils: they share the 12.38 in frame, the 11.024 in cutout and the 8.07 in mounting depth, and the motor clears the cabinet with 0.75 in to spare. One cabinet serves both coils: the D2 reads Qtc 1.077 with half power at 33.9 Hz, and the D4 reads Qtc 1.299 at 32.0 Hz. Run two of the same coil so the chambers match.

Any other 12, no. The airspace is worked out from the IDMAX12's own Qts and Vas, and a different woofer that happened to drop into the hole would not see the alignment printed on this page.

Image Dynamics' published Universal sealed airspace for the IDMAX12 V.4 is 1.25 cubic feet, and that is what this cabinet was solved to. At 41 inches wide the 8.07 inch motor sets the shallowest depth the cabinet can have, and at that depth each chamber holds 1.32 cubic feet net, slightly more. On this driver more air is the right direction: it brings Qtc down from 1.097 to 1.077 on the D2.

This is a high-Q sealed alignment and it is meant to be. The IDMAX12 V.4 publishes a Qts of 0.63 on the D2 and 0.76 on the D4, and a sealed system Q can never fall below the driver's own Qts however large the box. Reaching Qtc 0.707 on the D2 would take about 9.8 cubic feet per driver. What the higher Q buys is a rise around 44 Hz and half power at 32.0 to 33.9 Hz anechoic, before any cabin gain.

Image Dynamics rates the IDMAX12 V.4 at 500 watts RMS per driver, so target 350 to 500 watts RMS per driver at the final load, 700 to 1000 across the pair.

The IDMAX12 V.4 ships as a D2 or a D4. A pair of D2 drivers lands on 2 ohms with each woofer's coils in series and the two woofers in parallel, or 8 ohms all in series; all four coils in parallel is 0.5 ohm, which almost nothing is stable into. A pair of D4 drivers lands on 4 ohms with each woofer's coils in series and the woofers in parallel, or 1 ohm with everything in parallel. Use 1 ohm only if your amplifier is rated 1 ohm stable. Run a matched pair, both D2 or both D4. Confirm your amplifier's minimum stable impedance first.

41 inches across lets two 12 inch drivers sit side by side while the cabinet stays 15.14 inches deep at the base, so it spans a cargo floor instead of eating into it. The back panel rakes 20 degrees to sit flush against the rear seat.

The cargo area acts as an acoustic extension for the sealed box, and the cabin adds real output below 50 Hz, so in-vehicle response runs deeper than the anechoic 33.9 Hz on this page.

Two drivers sharing one sealed volume load each other: each driver's compression stroke becomes the pressure the other works against, which blurs the alignment either would have alone. A bonded full-height 3/4 inch divider gives each driver its own 1.32 cubic feet and its own polyfill.

It also means a failure in one driver does not unload the other, and the alignment on this page is the alignment in each chamber, not an average across a shared box.

Anechoic F3 is 33.9 Hz per chamber on the D2 at Qtc 1.077, and 32.0 Hz on the D4 at Qtc 1.299. Above Qtc 0.707 F3 sits below fc, so both carry a rise around their 44.4 Hz resonance before they roll off.

Those figures exclude cabin gain. In a vehicle 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 in both chambers 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, and on a driver with this Qts the shift is far too small to change the alignment.

No drivers. This is an enclosure only. You receive the cabinet finished in plush black carpet with the gloss black acrylic baffle insert, one side-mounted pre-wired terminal cup to both positions, the polyfill lining already in place, and stainless machine screws.

The threaded inserts are already pressed: Image Dynamics publishes an 11.614 inch bolt circle for the IDMAX12, so we drill to it at the shop. The pair of IDMAX12 V.4 is purchased separately.