Performance Optimized Down Fire Sealed Dual 12" Enclosure | Morel Ultimo PowerSlim PS124D Dual 12" Sealed enclosure

10.75 inches, which ties it as the tallest enclosure in the Proline X Down Fire line. This is not an under-seat build. It suits a cargo floor, a rear wall, or the space behind a bench seat. The footprint is the standard 30 by 15 inches, so it occupies no more floor area than any other Down Fire cabinet, it simply stands taller to give each of the two PS124D drivers its full 0.80 cubic feet.

If vertical clearance is your constraint, the single 12 inch PowerSlim enclosure at 6.375 inches or the dual 10 inch at 7.6875 inches are the alternatives.

Because two drivers in a shared sealed volume interact acoustically. Each driver's compression phase becomes the pressure environment the other driver is working against, which smears transient response and blurs the alignment each would have on its own. A full-height bonded 3/4 inch MDF divider eliminates that completely. Each PS124D gets its own 0.80 cubic feet net, matching Morel's own recommendation, plus its own polyfill. Separate chambers are the standing design rule on every Proline X dual sealed enclosure.

A 24 Hz free-air resonance paired with 49.4 liters of Vas. Those are the two parameters that set low frequency capability, and both are exceptional for a driver that mounts in 3.4 inches. Most shallow 12 inch subwoofers have a free-air resonance in the low to mid 30s, which caps how low they can go regardless of enclosure.

Morel achieved it through the double magnet EVC motor system and a suspension designed for long excursion in a short frame. The result in this cabinet is a predicted F3 of 34.2 Hz per driver, the deepest in the Proline X Down Fire line.

The enclosure uses one side-mounted Proline X terminal cup with a single pair of posts, pre-wired in 12 gauge OFC to both driver positions in parallel. You do not wire the two chambers separately at the amplifier.

Final impedance is set at the drivers. Each PS124D has dual 4 ohm voice coils, so you choose how to wire the two coils on each driver and that determines the load the amplifier sees through the cup. Wire both drivers identically, since mismatched wiring between chambers will split power unevenly. With 1400 watts RMS combined this cabinet demands a serious amplifier, so confirm the resulting load against its minimum stable impedance before powering the system.

Side mounted, and there is one cup serving both chambers rather than one per chamber. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup regardless of alignment, whether standard, wedge, or down fire. On this cabinet that keeps the connection fully accessible with the enclosure in its installed position, since both baffles face the floor. The cup is our Proline X ABS and carbon fiber composite unit, recessed, with stainless hardware, copper ring terminals, and pre-wired 12 gauge OFC.

Down Fire cabinets are built with square corners as a series standard. The 3 inch top down corner radius used on other Proline X alignments does not apply here. A down fire box is a low, wide platform that sits flat against a floor or cargo deck, and square corners maximize usable internal volume for a given footprint while keeping the cabinet stable on its mounting surface.

V-groove and dado joinery, CNC-cut on ShopSabre routers from Langboard Elite MDF. Every panel joint is a machined interlocking groove that mechanically locks the panels before adhesive is applied, which is what keeps both chambers airtight under sustained pressure cycling. The chamber divider is a full-height bonded 3/4 inch panel. Front baffles are double-layer at 1.5 inches, two bonded 3/4 inch sheets, at both driver positions, which matters with two 10.6 inch cutouts and 700 watt drivers bolted to them. Perimeter cross-bracing and pre-installed polyfill in each chamber complete the build. Assembled and inspected in Tullahoma, Tennessee.

No. This listing is for the enclosure only. Bring your own pair of Morel Ultimo PowerSlim PS124D subwoofers. The cutouts and mounting depth are direct fit at both driver positions.