Performance Optimized · Datasheet
Performance Optimized Down Fire Wide Sealed 12" Enclosure Morel Ultimo PowerSlim PS124D · Single 12" Sealed enclosure
- Net volume
- 0.800 cu ft after displacement and the brace
- Max mounting depth
- 3.386 in
- External dimensions
- 41 in W × 5.4375 in in the down fire position H × 14 in D
- Front baffle
- 1.5 in double baffle, outer layer machined as a flush recess
- Alignment: 0.800 cu ft net. Qtc 1.070, Fc 42.8 Hz, F3 32.7 Hz
- Down Fire Wide: 41"W x 14"D x 5.4375"H in down fire position, excludes the 1.75" standoffs (installed height 7.1875"). Stands lower than the standard 30 x 15 at 6.375"
- Height set by: airspace; 1.30" of clearance above the motor
- Driver: Morel Ultimo PowerSlim PS124D, DVC 4 ohm, 700W RMS / 2100W max, 11mm Xmax each way, 3.386" mounting depth, 24 Hz Fs
- Build: Langboard Elite MDF, V-groove and dado, 1.5" double baffle with flush outer recess, windowed U-brace, 12g OFC side-mounted terminal cup
Spec of record
Technical specifications
| Series | Proline X Performance Optimized Down Fire Wide |
|---|---|
| Compatible Driver | Morel Ultimo PowerSlim PS124D (DVC 4 ohm), quantity 1. Direct fit |
| Enclosure Type | Sealed, down fire, floor coupled |
| Intended Fitment | Long, low spaces where height or depth is the limit and 41 in of run is available |
| Firing Direction | Down firing. Feet ship uninstalled, so front or up firing is also possible |
| Chamber Configuration | Single chamber, windowed U-brace, one side-mounted terminal cup |
| External Width | 41 in |
| External Depth | 14 in |
| External Height | 5.4375 in in the down fire position, excludes standoffs |
| Installed Height | 7.1875 in including the 1.75 in standoffs |
| Dimension Reference | All external dimensions measured in down fire position |
| Standard 30 x 15 Version | 6.375 in tall, 0.80 cu ft net |
| Internal Volume, Gross | 0.888 cu ft |
| Internal Volume, Net | 0.800 cu ft after displacement and the brace |
| Height Set By | Airspace; 1.30 in clearance above the motor |
| Alignment | Qtc 1.070, Fc 42.8 Hz, F3 32.7 Hz anechoic |
| Woofer Opening | 10.6 in |
| Mounting Depth Required | 3.386 in |
| Frame Outer Diameter | 12.008 in |
| Driver Displacement | 0.08 cu ft, estimated; Morel publishes no displacement figure, so the 12 inch rule of thumb is used |
| Driver Fs | 24 Hz |
| Driver Qts | 0.6 - Qtc Cannot Fall Below This In Any Sealed Box |
| Driver Qes / Qms | 0.7 / 3.6 |
| Driver Vas | 49.4 Liters / 1.7 Cubic Feet |
| Driver Mms | 252.1 g |
| Driver BL | 9.1 |
| Driver Sd | 452.4 cm² |
| Driver Xmax | ±11mm |
| Driver DC Resistance | 1.6 Ohm (Coils In Parallel) |
| Driver Sensitivity | 83 dB (2.83V/1m) |
| Driver Power Handling | 700 Watts RMS / 2100 Watts Max Transient |
| Driver Frequency Response | 20-500 Hz |
| Driver Cone | Flat Honeycomb Hexatech Aluminium |
| Driver Voice Coil | 129.5mm / 5.1" | 4 Layers Carbon | Aluminium Former |
| Driver Motor | Double Magnet EVC |
| Voice Coil Configuration | Dual 4-Ohm | 2Ω Parallel or 8Ω Series At The Driver |
| Awards | EISA Best In-Car Subwoofer 2023-2024 (Ultimo PowerSlim Series) |
| Driver Mounting | 8/32 Threaded Inserts | Stainless Steel Machine Screws Included |
| Recommended Power | 350-700 Watts RMS (Morel Rated Range) |
| Material | Langboard Elite 3/4 in MDF |
| Joinery | V-groove and dado, CNC cut on ShopSabre routers |
| Front Baffle | 1.5 in double baffle, outer layer machined as a flush recess |
| Internal Bracing | Windowed U-brace, dadoed to the shell |
| Corner Profile | Square (Down Fire series standard) |
| Terminal Cup | One Proline X ABS and carbon fiber composite, side mounted, pre-wired 12 gauge OFC |
| Standoffs | 1.75 in, included, shipped uninstalled |
| Damping | Polyfill installed as a light wall lining |
| Carpet | Plush black |
| Bundle Options | Enclosure only (bring your own Morel PS124D) |
| Warranty | 1 year limited (enclosure) |
| Built In | Tullahoma, Tennessee, USA |
Modelled response
Performance in this enclosure
01Is it a sealed driver?
Efficiency bandwidth product places the motor before anything else is decided.
02What the box does to it
0.800 cu ft against a 49.4 L Vas.
03The 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 11.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 24.00 | Hz | free-air resonance |
| Qts | 0.600 | D4 | |
| Vas | 49.40 | L | equivalent compliance |
| Sd | 452.4 | cm² | effective piston area |
| Xmax | 11 | mm | one-way linear travel |
| Pe | 700 | W | continuous RMS |
| SPL | 81.7 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by Morel Ultimo PowerSlim owner's manual, rev 24-12-23. Curves computed against this enclosure’s actual net airspace.
From the shop floor
Installer's take
A full 12 in a cabinet 5.4375 inches tall. The PS124D mounts 3.386 inches deep, so on 41 by 14 the box drops below what the standard version needs.
Height was solved to the airspace: 5.4375 tall holds 0.800 net, against 0.80 in the standard box, and the motor clears the lid with 1.30 inches to spare. Same air, lower box.
At Morel's own 22.7 liters it lands at Qtc 1.070 with F3 32.7 Hz. The 24 Hz free-air resonance and 49.4 liter Vas are conventional driver numbers in a shallow frame.
700 watts RMS with 2100 of transient headroom, and the reason is the 5.1 inch voice coil. Dual 4 ohm, 2 ohms parallel or 8 ohms series at the driver. Target 350 to 700 watts RMS.
Measure installed height, not cabinet height: 5.4375 on its own, 7.1875 with the 1.75 inch feet on. The standard 30 by 15 is still the pick if you do not have 41 inches of run.
Before you order
Questions
Why is this cabinet 41 inches wide instead of 30?
Because it trades length for depth and height. The standard Performance Optimized Down Fire platform is 30 wide by 15 deep; this one is 14 deep, 1 inch shallower, and 41 long. Spreading the airspace along 11 more inches lets the cabinet stand 5.4375 inches tall instead of 6.375.
Fourteen inches of depth is the practical minimum, since a 12 inch frame needs about 13 inches of baffle. If your space is long and low rather than deep or tall, this is the shape that fits.
How does this compare to the standard 30 x 15 PS124D enclosure?
Same driver, different shape. The standard cabinet is 30 by 15 by 6.375 inches and holds 0.80 cubic feet net. This cabinet is 41 by 14 by 5.4375 inches and holds 0.800 cubic feet net.
The airspace is effectively the same, so the driver behaves the same way in either. Choose the standard box when length is limited; choose this one when height or depth is the limit and you have 41 inches of run.
How does a driver this shallow reach so low in a sealed box?
A 24 Hz free-air resonance paired with 49.4 liters of Vas. Most shallow 12s have a free-air resonance in the low to mid 30s, which caps how low they can go regardless of enclosure.
In this cabinet the PS124D lands at Qtc 1.070, Fc 42.8 Hz and a predicted F3 of 32.7 Hz, computed from Morel's published parameters.
How do I wire this enclosure and set my impedance?
One side-mounted Proline X terminal cup pre-wired in 12 gauge OFC. The PS124D has dual 4 ohm voice coils: parallel for a 2 ohm load, series for 8 ohms. Most single-driver builds run 2 ohms.
Morel rates this driver for 350 to 700 watts RMS. Confirm your amplifier is stable at your chosen load and set gains within that range.
Where is the terminal cup located on a down fire enclosure?
Side mounted. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup, whether standard, wedge or down fire, which keeps the connection accessible with the baffle facing 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.
Why are the corners square instead of radiused?
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, long 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.
How is this enclosure built?
V-groove and dado joinery, CNC cut on ShopSabre routers from Langboard Elite MDF. Every panel joint is a machined interlocking groove that locks the panels before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling. The front baffle is a 1.5 inch double layer, the outer layer machined as a flush recess around the 10.6 inch cutout.
A windowed U-brace stiffens the long panels, and polyfill is installed as a light wall lining. Do not add more fill; packing a sealed box makes it act larger and moves the alignment off the 0.800 cubic feet it was built to. Assembled and inspected in Tullahoma, Tennessee.
Is the Morel PS124D subwoofer included with this enclosure?
No. This listing is for the enclosure only. Bring your own Morel Ultimo PowerSlim PS124D. The cutout and mounting depth are direct fit.
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