

Performance Optimized · Datasheet
Performance Optimized Down Fire Sealed Dual 12" Enclosure Musway MG12 · Dual 12" Sealed enclosure
- Net volume
- 1.30 cu ft per chamber after the divider and the driver displacement
- Max mounting depth
- 7.13 in required, 7.93 in clearance above the motor
- External dimensions
- 30.00 in W × 15.81 in in the down fire position H × 15.00 in D
- Front baffle
- 1.5 in double baffle, outer layer machined as a flush recess
- Alignment: 1.30 cu ft net per chamber, Qtc 0.66, F3 53.3 Hz
- Drivers: Pair of Musway MG12 (dual 2 ohm), 700 W RMS each, 22 mm Xmax, 7.13 in mounting depth
- Chambers: Two fully separate sealed chambers, 3/4" MDF full divider, one shared side-mounted terminal cup
- Standoffs: Included, 1.75 in, shipped uninstalled. Installed height near 17.56 in
- Cabinet: 30.00"W x 15.00"D x 15.81"H in down fire position, excludes standoffs, square corners
Spec of record
Technical specifications
| Specification | Value |
|---|---|
| Series | Proline X Performance Optimized Down Fire |
| Compatible Driver | Musway MG12 (dual 2 ohm), quantity 2. Direct fit |
| Configuration | Dual 12 inch, two separate chambers, sealed down fire |
| Mounting Position | Trunk or cargo floor, baffle facing down on standoffs |
| Firing Direction | Downward. Feet ship uninstalled, so front or up firing is also possible |
| External Width | 30.00 in |
| External Depth | 15.00 in |
| External Height | 15.81 in in the down fire position, excludes standoffs |
| Installed Height | 17.56 in including the 1.75 in standoff |
| Internal Volume, Gross | 2.91 cu ft total |
| Internal Volume, Net Acoustic | 1.30 cu ft per chamber after the divider and the driver displacement |
| Height Set By | Airspace; clearance alone would allow a lower cabinet |
| Driver Mounting Depth | 7.13 in required, 7.93 in clearance above the motor |
| Floor Slot | 0.75 times the cone area at the 1.75 in standoff |
| Alignment, dual 2 ohm per chamber | Qtc 0.660, fc 49.5 Hz, F3 53.3 Hz anechoic |
| Woofer Opening | 11.22 in, two, Musway's published cutout |
| Frame Outer Diameter | 12.76 in |
| Bolt Circle | Not printed by Musway; threaded insert kit included |
| Driver Displacement | 0.117 cu ft, estimated; Musway publishes none |
| dual 2 ohm Fs / Qts / Qes / Qms / Vas | 30 Hz / 0.4 / 0.46 / 3.28 / 63.4 L |
| Driver Sd | 531 cm2, Musway spec |
| Xmax | 22 mm one way, Musway spec |
| Driver Power Handling | 700 W RMS per driver |
| Wiring Options | Musway sells the MG12 as dual 2 ohm; a matched pair should share a coil. A pair of dual 2 ohm drivers lands on 2 ohms with each woofer's coils in series and the two woofers in parallel, or 8 ohms all in series. Anything under 1 ohm, and many amplifiers at 1 ohm, is outside what the amplifier is built for, so series wiring is the safe default. |
| Parameter Source | Musway MG8 / MG10 / MG12 owner's manual specifications table; Vas taken as 63.4 L from Musway's own moving mass, printed 87.5 L |
| Material | Langboard Elite MDF |
| Construction | CNC cut, V-groove and dado joinery, square corners |
| Panel Thickness | 0.75 in |
| Front Baffle | 1.5 in double baffle, outer layer machined as a flush recess |
| Internal Bracing | Full-height 3/4 in divider |
| Driver Mounting | Threaded insert kit included, NOT pre-installed: Musway prints no bolt circle |
| Terminal Cups | One Proline X ABS and carbon fiber composite, side mounted, pre wired 12 gauge OFC to both driver positions |
| Standoffs | Included, 1.75 in, shipped uninstalled |
| Damping | Light polyfill wall lining in both chambers, does not alter acoustic volume |
| Carpet | Plush black |
| Shipping Weight | 52 lb |
| Warranty | 1 Year Limited |
| Built In | Tullahoma, Tennessee |
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
1.30 cu ft against a 63.4 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 22.0 mm — and a bigger one once a subsonic filter stops it wasting travel below the passband.
| Param | Value | Unit | Note |
|---|---|---|---|
| Fs | 30.00 | Hz | free-air resonance |
| Qts | 0.400 | D2 | |
| Vas | 63.40 | L | equivalent compliance |
| Sd | 531.0 | cm² | effective piston area |
| Xmax | 22 | mm | one-way maximum, as Musway publish it |
| Pe | 700 | W | continuous RMS |
| SPL | 87.6 | dB | 1 W / 1 m, derived from T/S |
Driver parameters as published by Musway published T/S table. Curves computed against this enclosure’s actual net airspace.
From the shop floor
Installer's take
1.30 cubic feet per chamber: Qtc 0.660 on the dual 2 ohm, F3 53.3 Hz.
Measure the installed height, not the cabinet height: 15.81 tall on its own, 17.56 with the standoffs on the 30 by 15 footprint.
Floor slot is 0.75 times the cone area at the 1.75 standoff, under the 1.0 I like. For hard use, taller feet or front firing.
Musway's MG12 table disagrees with itself: the printed 87.5 L Vas does not match the 174 g moving mass, so I built on the 63.4 L that the mass implies. Displacement is estimated.
Inserts ship in the kit, not pressed: Musway prints no bolt circle. Mark from the driver, drill, press. Sealed, so leave the polyfill as it is and run it at 700 watts or under per driver.
Before you order
Questions
Does this fit the Musway MG12, and will any other 12 inch fit?
The MG12, yes, in the dual 2 ohm version. The baffle is cut to 11.22 in, Musway's published cutout, under the 12.76 in frame. The 7.13 inch motor clears the cabinet with 7.93 inch to spare. Run two of the same coil so the chambers match.
Any other 12, no. The airspace is engineered around the MG12'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.
Why 1.30 cubic feet per chamber, and what alignment does it target?
1.30 cubic feet net per chamber on Musway's published figures: the dual 2 ohm reads Qtc 0.660 with resonance at 49.5 Hz and half power at 53.3 Hz. The volume is 1.3 cubic feet, a little above Musway's 35 litre (1.24 cubic foot) recommended sealed maximum for the MG12. That is a slightly over-damped alignment: a gentle, early rolloff and tight transients rather than a flat top.
Cabinet gain in a vehicle lifts the bottom end further, so in the car this reads deeper than the anechoic figures.
What amplifier power should I run, and how should I wire it?
Musway rates the MG12 at 700 watts RMS per driver, so target 489 to 700 watts RMS per driver at the final load.
Musway sells the MG12 as dual 2 ohm; a matched pair should share a coil. A pair of dual 2 ohm drivers lands on 2 ohms with each woofer's coils in series and the two woofers in parallel, or 8 ohms all in series. Anything under 1 ohm, and many amplifiers at 1 ohm, is outside what the amplifier is built for, so series wiring is the safe default. Confirm your amplifier's minimum stable impedance first.
How tall is this once the standoffs are on?
The cabinet is 15.81 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 17.56 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.
Why two separate chambers instead of one shared volume?
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 1.30 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.
What is the expected low-frequency extension?
Anechoic F3 is 53.3 Hz per chamber. 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.
Do I need to add polyfill or damping?
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, which walks the alignment away from the 1.30 cubic feet per chamber this cabinet was built to.
Is the driver included, and are the threaded inserts installed?
No driver. This is an enclosure only. You receive the cabinet finished in plush black carpet, one side-mounted pre-wired terminal cup to both positions, the polyfill lining already in place, the standoffs, and a threaded insert kit with stainless machine screws.
The inserts ship loose on purpose: Musway prints no bolt circle for the MG12, so you set the driver in the recess, mark its holes, drill and press the inserts. The pair of Musway MG12 is purchased separately, and the cabinet is cut direct fit to it, not a general purpose 12 inch box.
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