{"product_id":"performance-optimized-down-fire-wide-sealed-12-enclosure-hertz-mille-pro-mps-300","title":"Performance Optimized Down Fire Wide Sealed 12\" Enclosure | Hertz Mille Pro MPS 300","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 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td.on{background:rgba(184,115,51,.10);color:#d6d3d1}.df-tier tr:last-child td{border-bottom:none}@media(max-width:600px){.df-hero h2{font-size:1.7em}.df-section,.df-enc,.df-cta,.df-hero{padding-left:20px;padding-right:20px}}\u003c\/style\u003e\n\u003cdiv 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 Hertz Mille Pro MPS 300, S2 or S4\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\"\u003e16.8mm Xmax\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\"\u003e0.800\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\"\u003e1.002\u003c\/span\u003e\u003cspan class=\"l\"\u003esystem Qtc, MPS 300 S2\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e37.0 Hz\u003c\/span\u003e\u003cspan class=\"l\"\u003eF3 rolloff, MPS 300 S2\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e5.4375 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 Hertz Mille Pro MPS 300 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 Hertz Mille Pro MPS 300 frame measures 12.532 inches across and sits on the 14 inch deep baffle with about 0.73 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\u003e5.4375 inches tall\u003c\/strong\u003e, against 6.375 for the standard 30 x 15 Hertz Mille Pro MPS 300 cabinet, both measured in the down fire position without feet. That is 0.9375 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 7.1875 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 cutout, the cabinet height and the airspace all come from the Hertz Mille Pro MPS 300'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 MPS 300\u003c\/h3\u003e\n\u003cp\u003eThe baffle is bored to the Hertz \u003cstrong\u003e283mm cutout\u003c\/strong\u003e, 11.14 inches, and the internal height clears the driver's \u003cstrong\u003e3.465 inch mounting depth\u003c\/strong\u003e with 1.223 inches to spare. The result is a full 12 in a cabinet that stands \u003cstrong\u003e5.4375 inches tall\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eThe MPS 300 carries \u003cstrong\u003e16.8mm of Xmax\u003c\/strong\u003e, an unusually high figure for a shallow driver, on a polypropylene cone with a 38mm voice coil and a high density flux ferrite motor. It is rated 500 watts RMS and 1000 watts peak. Hertz includes a mesh grille in the box that can be rotated 90 degrees or removed.\u003c\/p\u003e\n\u003cp\u003eWhat makes this driver reach is the suspension: a \u003cstrong\u003e24 Hz free-air resonance on the S2 with 64.9 liters of Vas\u003c\/strong\u003e, and 23 Hz with 62.1 liters on the S4. Both models are single voice coil, so impedance is fixed by the model: 2 ohms on the \u003cstrong\u003eMPS 300 S2\u003c\/strong\u003e, 4 ohms on the \u003cstrong\u003eMPS 300 S4\u003c\/strong\u003e. Hertz states Fs, Vas and Qts are unchanged between parallel and series measurement, so one cabinet is correct either way.\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\u003e0.800 cubic feet net\u003c\/strong\u003e, from 0.888 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 0.80 cubic feet net, and the motor clears the top panel with 1.223 inches to spare. Same air, same alignment, lower cabinet.\u003c\/p\u003e\n\u003cp\u003eComputed from Hertz's published Thiele-Small parameters: \u003cstrong\u003eMPS 300 S2: Qtc 1.002, Fc 47.2 Hz, F3 37.0 Hz\u003c\/strong\u003e; \u003cstrong\u003eMPS 300 S4: Qtc 0.812, Fc 44.5 Hz, F3 39.5 Hz\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eThat matches Hertz's own sealed recommendation of 22.7 liters. Pay attention to the model choice, because \u003cstrong\u003eit reverses from the 10 inch MPS 250\u003c\/strong\u003e: on the MPS 300 the S4 is the better damped driver, Qts 0.42 against 0.51, with far more motor force, 18.7 T·m against 12.3. The S4 is the controlled alignment; the S2 reaches about 2.5 Hz deeper with a modest lift at the corner.\u003c\/p\u003e\n\u003cp\u003eHertz's published enclosure data reconciles with its own T\/S parameters: run their Qts and Vas through standard sealed box math at their recommended volume and the corner frequency comes back where they print it. That is not true of every manufacturer in this category.\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 5.4375 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 7.1875 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\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eDown Firing Into the Floor\u003c\/h3\u003e\n\u003cp\u003eThe driver fires downward into the floor and the cabinet couples to the surface it sits on. The sealed rolloff meets rising cabin gain below 60 Hz, so in-car response extends below the anechoic figures quoted above.\u003c\/p\u003e\n\u003cp\u003eFor sealed applications Hertz suggests a \u003cstrong\u003e15 Hz subsonic filter at 24 dB per octave\u003c\/strong\u003e and a 70 to 80 Hz low pass, also at 24 dB per octave. Those are the manufacturer's own recommended settings for this driver.\u003c\/p\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\u003eThe MPS 300 is rated \u003cstrong\u003e500 watts RMS and 1000 watts peak\u003c\/strong\u003e on a 38mm voice coil. Since both models are single voice coil, the load your amplifier sees is decided when you choose the S2 or the S4. Check what your amplifier is stable into before you order the driver.\u003c\/p\u003e\n\u003cp\u003eThe enclosure carries a 1 year limited warranty. Bring your own MPS 300 S2 or MPS 300 S4; 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":47345340219481,"sku":"PO 12-S DFW MPS","price":319.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0689\/1389\/files\/PO_12_S_DFW_MPS_Front.jpg?v=1790650563","url":"https:\/\/audiointensity.com\/products\/performance-optimized-down-fire-wide-sealed-12-enclosure-hertz-mille-pro-mps-300","provider":"Audio Intensity","version":"1.0","type":"link"}