{"product_id":"performance-optimized-down-fire-wide-sealed-12-enclosure-diamond-audio-dmd-sh","title":"Performance Optimized Down Fire Wide Sealed 12\" Enclosure | Diamond Audio DMD-SH","description":"\u003cstyle\u003e.df-wrap{font-family:'Helvetica Neue',Arial,sans-serif;line-height:1.75;color:#d6d3d1;max-width:1100px;margin:0 auto;background:#0c0a09}.df-wrap *{box-sizing:border-box}.df-hero{background:linear-gradient(135deg,#0c0a09 0%,#5c3317 100%);padding:54px 36px;text-align:center;color:#fff}.df-hero h2{font-size:2.3em;font-weight:800;text-transform:uppercase;letter-spacing:1.5px;margin:0 0 12px;color:#fff}.df-hero p{font-size:1.1em;font-weight:300;opacity:.93;margin:0 0 22px;color:#d6d3d1}.df-badges{display:flex;justify-content:center;flex-wrap:wrap;gap:10px}.df-badge{background:rgba(184,115,51,.18);border:1px solid #b87333;color:#e8b98d;padding:7px 16px;border-radius:18px;font-size:.8em;font-weight:600}.df-stats{display:flex;flex-wrap:wrap;background:#1c1917}.df-stat{flex:1 1 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class=\"df-wrap\"\u003e\n\u003cdiv class=\"df-hero\"\u003e\n\u003ch2\u003eProline X Performance Optimized Down Fire Wide 12\" Sealed\u003c\/h2\u003e\n\u003cp\u003eCut for the Diamond Audio DMD-SH 12, DMD122SH or DMD124SH\u003c\/p\u003e\n\u003cdiv class=\"df-badges\"\u003e\n\u003cspan class=\"df-badge\"\u003eDown Fire Wide\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003eV-Groove and Dado\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003e14\" Depth\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003e3 Inch Mounting Depth\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stats\"\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e1.252\u003c\/span\u003e\u003cspan class=\"l\"\u003ecu ft net\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e1.052\u003c\/span\u003e\u003cspan class=\"l\"\u003esystem Qtc, DMD122SH\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e48.4 Hz\u003c\/span\u003e\u003cspan class=\"l\"\u003eF3 rolloff, DMD122SH\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e7.0625 in\u003c\/span\u003e\u003cspan class=\"l\"\u003ecabinet height, excludes feet\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eThe Down Fire Wide Format\u003c\/h3\u003e\n\u003cp\u003eDown Fire Wide is the same driver in a different shape. The standard Performance Optimized Down Fire cabinet for the Diamond Audio DMD-SH 12 is 30 by 15 inches. This one runs \u003cstrong\u003e41 inches wide by 14 inches deep\u003c\/strong\u003e: 1 inch shallower front to back and 11 inches longer.\u003c\/p\u003e\n\u003cp\u003eFourteen inches is not arbitrary. A 12 inch frame needs about 13 inches of baffle to sit on, so 14 is the practical minimum depth for this driver size. The Diamond Audio DMD-SH 12 frame measures 12.83 inches across and sits on the 14 inch deep baffle with about 0.58 inches of baffle fore and aft. \u003c\/p\u003e\n\u003cp\u003eSpreading the airspace along 41 inches instead of 30 means the cabinet does not have to climb to find it. This box stands \u003cstrong\u003e7.0625 inches tall\u003c\/strong\u003e, against 8.3125 for the standard 30 x 15 Diamond Audio DMD-SH 12 cabinet, both measured in the down fire position without feet. That is 1.25 inches lower.\u003c\/p\u003e\n\u003cdiv class=\"df-highlight\"\u003e\n\u003cp\u003e\u003cstrong\u003eWhich one to choose.\u003c\/strong\u003e The standard 30 x 15 is the pick when length is limited. This one is the pick when height or depth is the limit and you have 41 inches of run. With the 1.75 inch feet installed this cabinet stands 8.8125 inches, so measure for that.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003ePerformance, Performance Optimized, and Micro\u003c\/h3\u003e\n\u003cp\u003eProline X builds three tiers of Down Fire enclosure. The difference is not finish or materials, it is whether the cabinet was designed for a category or for a driver, and how much of the fitting work is already done for you.\u003c\/p\u003e\n\u003cdiv class=\"df-tier\"\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003e \u003c\/th\u003e\n\u003cth\u003ePerformance\u003c\/th\u003e\n\u003cth class=\"on\"\u003ePerformance Optimized\u003c\/th\u003e\n\u003cth\u003eMicro Series\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eFitment\u003c\/td\u003e\n\u003ctd\u003eUniversal. Accepts any subwoofer that clears the published cutout and mounting depth.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eWoofer specific. Cut for one named subwoofer, with cutout, mounting depth, magnet clearance and displacement drawn in CAD from that driver.\u003c\/td\u003e\n\u003ctd\u003eWoofer specific. Cut for one named subwoofer.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eFootprint\u003c\/td\u003e\n\u003ctd\u003eSized to the driver diameter. 24.5 by 13.5 inches on the 10 inch.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eShared 30 by 15 inch platform on most builds. Down Fire Wide variants like this one run long and shallow for under seat fitment.\u003c\/td\u003e\n\u003ctd\u003eCompact per driver footprint. 21.5 by 14.5 inches on the 10 inch.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eFront baffle\u003c\/td\u003e\n\u003ctd\u003eSingle, 3\/4 inch.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eDouble layer, outer layer machined as a flush recess. 1.5 inch.\u003c\/td\u003e\n\u003ctd\u003eDouble, 1.5 inch.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eDriver mounting\u003c\/td\u003e\n\u003ctd\u003eSolid flange. You drill your own mounting holes.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003e8\/32 threaded inserts, stainless machine screws included.\u003c\/td\u003e\n\u003ctd\u003e8\/32 threaded inserts, stainless machine screws included.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eJoinery\u003c\/td\u003e\n\u003ctd\u003eV-groove and dado, CNC cut.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eV-groove and dado, CNC cut, perimeter cross brace.\u003c\/td\u003e\n\u003ctd\u003eStack fab, dowel reinforced.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003ePublished alignment\u003c\/td\u003e\n\u003ctd\u003eModeled Qtc profiles across a range of drivers. No single response curve.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eA real predicted Qtc and F3 for that exact driver, calculated from its own Thiele-Small parameters.\u003c\/td\u003e\n\u003ctd\u003eTarget alignment described in the listing.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eCarpet\u003c\/td\u003e\n\u003ctd\u003eGray standard, black optional.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003ePlush black.\u003c\/td\u003e\n\u003ctd\u003ePlush black.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"a\"\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e1 year limited.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003e1 year limited.\u003c\/td\u003e\n\u003ctd\u003e2 years.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-note\"\u003e\u003cp\u003e\u003cstrong\u003eFeet ship with every tier, uninstalled on purpose.\u003c\/strong\u003e Mount them where your floor wants them for a down fire install, or leave them off and run the cabinet front firing or up firing. The orientation is yours to choose.\u003c\/p\u003e\u003c\/div\u003e\n\u003cdiv class=\"df-note\"\u003e\u003cp\u003e\u003cstrong\u003eThis page is a Performance Optimized enclosure.\u003c\/strong\u003e The airspace, the cutout and the cabinet height all come from the Diamond Audio DMD-SH 12's own published numbers. A Performance box fits your subwoofer. A Performance Optimized box was built for it.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eBuilt Around the DMD-SH 12\u003c\/h3\u003e\n\u003cp\u003eThe baffle is bored to the DMD-SH 12's \u003cstrong\u003e11.06 inch cutout\u003c\/strong\u003e, and the driver needs only a \u003cstrong\u003e3.00 inch mounting depth\u003c\/strong\u003e, so the motor clears the top panel with 3.312 inches to spare. Cabinet height here is set by the airspace, not the driver.\u003c\/p\u003e\n\u003cp\u003eDiamond builds the DMD-SH on a die-cast shallow frame with a high-strength paper cone and an \u003cstrong\u003ealuminum heatsink dust cap\u003c\/strong\u003e that pulls heat away from the coil. The pole is vented, the spider carries woven tinsel leads, terminals are oversized push type, and a wrap-around ABS gasket seals the flange against the baffle. Diamond states the motor and suspension symmetry are Klippel optimized.\u003c\/p\u003e\n\u003cp\u003eTwo coil configurations: the \u003cstrong\u003eDMD122SH\u003c\/strong\u003e, dual 2 ohm, and the \u003cstrong\u003eDMD124SH\u003c\/strong\u003e, dual 4 ohm. Both share the mounting depth and cutout, so this cabinet is a direct fit for either. Both are rated 300 watts RMS and 600 watts maximum.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eNet Volume and Alignment\u003c\/h3\u003e\n\u003cp\u003eThe cabinet holds \u003cstrong\u003e1.252 cubic feet net\u003c\/strong\u003e, from 1.34 cubic feet gross after the brace and the driver's 0.08 cubic feet of displacement (estimated, no manufacturer figure).\u003c\/p\u003e\n\u003cp\u003eHeight is the free dimension. With the footprint fixed at 41 by 14, the cabinet height was solved to put the cabinet on the same airspace as the standard 30 x 15 box, which holds 1.213 cubic feet net, and the motor clears the top panel with 3.312 inches to spare. Same air, same alignment, lower cabinet.\u003c\/p\u003e\n\u003cp\u003eComputed from the Thiele-Small parameters Diamond publishes: \u003cstrong\u003eDMD122SH: Qtc 1.052, Fc 62.8 Hz, F3 48.4 Hz\u003c\/strong\u003e; \u003cstrong\u003eDMD124SH: Qtc 1.246, Fc 63.7 Hz, F3 46.4 Hz\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eCoil choice matters on this driver. The \u003cstrong\u003eDMD122SH\u003c\/strong\u003e runs a Qts of 0.77 with 13.7 T of motor force and 7.9mm of Xmax; the \u003cstrong\u003eDMD124SH\u003c\/strong\u003e runs 0.91 with 16.4 T and 8.8mm. System Qtc can never fall below the driver's own Qts, so the D4 is underdamped in any sealed box. It reaches about 2 Hz lower here with more lift at the corner; the D2 is the better damped of the two.\u003c\/p\u003e\n\u003cp\u003eFree-air resonance is 46.0 Hz on the D2 and 46.5 Hz on the D4, so F3 sits in the high 40s regardless of volume. This is a punch and midbass driver in a shallow package, not a deep extension driver. Firing down into the floor, the sealed rolloff meets rising cabin gain below 60 Hz.\u003c\/p\u003e\n\u003cp\u003eDiamond suggests 0.75 gross for this driver, and we build larger on purpose: the extra air is better damped on both coils. Our figures will not match Diamond's enclosure table, because that table does not reconcile with the Thiele-Small parameters printed beside it. We publish what the driver data gives.\u003c\/p\u003e\n\u003cdiv class=\"df-highlight\"\u003e\n\u003cp\u003e\u003cstrong\u003eTrue net, not marketing net.\u003c\/strong\u003e Internal volume is calculated from the machined cavity dimensions and the driver's displacement, not estimated from external dimensions minus wall thickness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eDown Fire Wide Construction\u003c\/h3\u003e\n\u003cp\u003eCut with V-groove and dado joinery on our ShopSabre routers from Langboard Elite 3\/4 inch MDF, a dense 48.5 lb\/ft³ board with a 200 psi internal bond and 410,000 psi MOE. Every panel joint is a machined interlocking groove that mechanically locks before adhesive is applied, which keeps the cabinet airtight under sustained pressure cycling. Corners are square on Down Fire cabinets.\u003c\/p\u003e\n\u003cp\u003eThe cabinet measures \u003cstrong\u003e41 inches wide by 14 inches deep by 7.0625 inches tall, measured in the down fire position\u003c\/strong\u003e. Feet ship with the enclosure but are not installed. With the 1.75 inch feet on, the cabinet stands 8.8125 inches, so plan the space around where you intend to mount them.\u003c\/p\u003e\n\u003cdiv class=\"df-grid\"\u003e\n\u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003e1.5 Inch Double Baffle\u003c\/h4\u003e\n\u003cp\u003eTwo \u003cstrong\u003e3\/4 inch layers laminated to 1.5 inches\u003c\/strong\u003e, with the outer layer machined as a flush recess so the driver bolts to the inner layer. 8\/32 threaded inserts at the driver position, stainless machine screws included.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eWindowed U-Brace\u003c\/h4\u003e\n\u003cp\u003eA \u003cstrong\u003ewindowed U-brace\u003c\/strong\u003e dadoed to the shell ties the long 41 inch panels together without taking a meaningful bite out of the airspace.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eSide-Mounted Terminal Cup\u003c\/h4\u003e\n\u003cp\u003eProline X ABS and carbon fiber composite cup with stainless hardware and copper ring terminals, pre-wired in \u003cstrong\u003e12 gauge OFC\u003c\/strong\u003e. Side mounted so it stays accessible with the baffle facing the floor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003ePolyfill Installed\u003c\/h4\u003e\n\u003cp\u003ePolyfill is installed as a light wall lining to control internal reflections. It does not change the acoustic volume, so do not add more.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- ENCLOSURE PERFORMANCE SLOT --\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003ePower and Warranty\u003c\/h3\u003e\n\u003cp\u003eDiamond rates the DMD-SH 12 at \u003cstrong\u003e300 watts RMS and 600 watts maximum\u003c\/strong\u003e. Both coil variants are dual voice coil, so you set final impedance at the driver: series or parallel, whichever your amplifier is stable into.\u003c\/p\u003e\n\u003cp\u003eThe enclosure carries a 1 year limited warranty. Bring your own DMD122SH or DMD124SH; the driver is purchased separately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-cta\"\u003e\n\u003ch3\u003eCut for the Driver, Not the Catalog\u003c\/h3\u003e\n\u003cp\u003eDown Fire Wide, 41 inches long and 14 deep, cut for one driver model and built one at a time in Tullahoma, Tennessee. Questions on fitment or amplifier matching, call us at 931-563-5151.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Proline X","offers":[{"title":"Default Title","offer_id":47345339564121,"sku":"PO 12-S DFW DMD","price":319.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0689\/1389\/files\/PO_12_S_DFW_DMD_Front.jpg?v=1790650532","url":"https:\/\/audiointensity.com\/products\/performance-optimized-down-fire-wide-sealed-12-enclosure-diamond-audio-dmd-sh","provider":"Audio Intensity","version":"1.0","type":"link"}