{"product_id":"performance-optimized-down-fire-sealed-12-enclosure-jl-audio-12w3v3-4","title":"Performance Optimized Down Fire Sealed 12\" Enclosure | JL Audio 12W3v3-4","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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td{border-bottom:none}.df-opt td{background:#14532d;color:#fff;font-weight:600}.df-char{display:block;font-size:.78em;color:#a8a29e;font-weight:400;margin-top:2px}.df-opt .df-char{color:#86efac}.df-graph{background:#0c0a09;border:1px solid #44403c;border-radius:8px;padding:14px;margin:18px 0}.df-graph-title{font-size:.78em;font-weight:700;letter-spacing:1px;text-transform:uppercase;color:#a8a29e;margin:0 0 10px}.df-legend{display:flex;flex-wrap:wrap;gap:12px;margin-top:10px}.df-legend-item{display:flex;align-items:center;gap:6px;font-size:12px;color:#a8a29e}.df-sw{width:22px;height:3px;border-radius:2px;display:inline-block}.df-note{background:#292524;border:1px solid #44403c;border-radius:8px;padding:14px 16px;margin-top:6px}.df-note p{margin:0;color:#d6d3d1;font-size:13.5px;line-height:1.6}.df-link{color:#d99058;text-decoration:underline}.df-cta{background:linear-gradient(135deg,#0c0a09 0%,#5c3317 100%);padding:40px 36px;text-align:center;color:#fff}.df-cta h3{color:#fff;font-size:1.4em;margin:0 0 10px;border:none;padding:0}.df-cta p{opacity:.92;margin:0 auto;max-width:640px;color:#d6d3d1}@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 PO Down Fire 12\" Sealed\u003c\/h2\u003e\n\u003cp\u003eCut and tuned for the JL Audio 12W3v3-4\u003c\/p\u003e\n\u003cdiv class=\"df-badges\"\u003e\n\u003cspan class=\"df-badge\"\u003eV-Groove and Dado\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003eLangboard Elite MDF\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003e1.23 cu ft Net\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003eMilled Magnet Relief\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\"\u003e1.23\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\"\u003e0.808\u003c\/span\u003e\u003cspan class=\"l\"\u003esystem Qtc\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e43.3 Hz\u003c\/span\u003e\u003cspan class=\"l\"\u003eF3 rolloff\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e8.3125 in\u003c\/span\u003e\u003cspan class=\"l\"\u003ecabinet height\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eBuilt Around the 12W3v3-4\u003c\/h3\u003e\n\u003cp\u003eNothing about this cabinet is generic. The baffle is bored to the 12W3v3-4's \u003cstrong\u003e11.0625 inch cutout\u003c\/strong\u003e, 281mm to JL's spec, and the internal height is set by the driver's \u003cstrong\u003e6.65 inch mounting depth\u003c\/strong\u003e. Overall frame diameter is 12.5 inches, which the 30 by 15 inch footprint carries with the terminal cup clear of the driver.\u003c\/p\u003e\n\u003cp\u003eThe W3v3 is JL's medium power 12, a single voice coil driver at 4 ohms nominal rated \u003cstrong\u003e500 watts RMS\u003c\/strong\u003e with a recommended amplifier range of 150 to 500 watts. The cone is mineral filled polypropylene on a rubber surround, 80.6 square inches of piston area, with 13.0mm of one way linear excursion. Sensitivity is \u003cstrong\u003e87.15 dB at 1 watt and 1 meter\u003c\/strong\u003e, genuinely efficient by the standards of this program. Dynamic Motor Analysis handles linearity and Elevated Frame Cooling handles heat.\u003c\/p\u003e\n\u003cp\u003eThe published parameters are what make this driver unusual: \u003cstrong\u003eFs 26.72 Hz, Qts 0.444 and Vas 2.844 cubic feet\u003c\/strong\u003e. That Vas is the largest of any driver in the Proline X Down Fire line. A large Vas means a compliant suspension, so the driver wants real volume before the enclosed air starts dominating the alignment, and the low Qts leaves headroom to reach a well damped result.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eNet Volume, Not Gross\u003c\/h3\u003e\n\u003cp\u003eWe build this cabinet at \u003cstrong\u003e1.23 cubic feet net\u003c\/strong\u003e from 1.30 gross, after panel thickness, perimeter bracing and the driver's published 0.071 cubic feet of displacement are accounted for. That produces \u003cstrong\u003eQtc 0.808, Fc 48.6 Hz and a predicted F3 of 43.3 Hz\u003c\/strong\u003e. JL Audio's recommended sealed volume is 1.125 cubic feet.\u003c\/p\u003e\n\u003cp\u003eThe cabinet runs slightly larger because the driver's depth sets the floor. Take 6.65 inches of mounting depth, subtract the 3\/4 inch recovered by the flush recess in the outer baffle layer, subtract the 3\/8 inch milled relief behind the magnet, then add half an inch of clearance behind the motor. Minimum internal height lands at 6.0625 inches, which on this footprint is 1.23 net. The extra volume works in your favor: at JL's 1.125 the system computes near Qtc 0.834, and at 1.23 it lands at 0.808.\u003c\/p\u003e\n\u003cdiv class=\"df-highlight\"\u003e\u003cp\u003e\u003cstrong\u003eTrue net, not marketing net.\u003c\/strong\u003e Internal volume is calculated from the machined cavity dimensions and the driver's published displacement, not estimated from external dimensions minus wall thickness.\u003c\/p\u003e\u003c\/div\u003e\n\u003cp\u003eWorth stating plainly, because of that 2.844 cubic foot Vas this driver would reach the textbook 0.707 alignment at roughly \u003cstrong\u003e1.85 cubic feet net\u003c\/strong\u003e, which on a 30 by 15 footprint is a cabinet near 11 inches tall. That is outside the Down Fire format. In a down fire cabinet 0.808 is the right answer: a mild lift near the corner frequency and a usable, well behaved alignment. If flat response is the priority and you have the vertical space, contact us about a taller custom build.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eDown Fire 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\u003eA down fire box is a low, wide platform that sits flat against a floor or cargo deck, so square corners maximize usable internal volume for a given footprint and keep the cabinet stable on its mounting surface. Perimeter cross-bracing ties the panels together, polyfill is pre-installed, and the driver lands on 8\/32 threaded inserts with stainless machine screws included. External dimensions are \u003cstrong\u003e30 inches wide by 15 inches deep by 8.3125 inches high\u003c\/strong\u003e, measured in the down fire position, at 34 pounds.\u003c\/p\u003e\n\u003cp\u003eFiring down into the floor, the sealed rolloff meets rising cabin gain below 60 Hz, so in-car response extends well below the anechoic figure.\u003c\/p\u003e\n\u003cdiv class=\"df-grid\"\u003e\n\u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eDouble Baffle, Flush Recess\u003c\/h4\u003e\n\u003cp\u003eThe front baffle is \u003cstrong\u003e1.5 inches\u003c\/strong\u003e, two bonded 3\/4 inch sheets, with the outer layer machined as a flush recess so the driver bolts to the inner layer. That recovers 3\/4 inch of internal clearance, which matters with an 11.0625 inch cutout.\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\u003eMilled Magnet Relief\u003c\/h4\u003e\n\u003cp\u003eA \u003cstrong\u003e3\/8 inch deep\u003c\/strong\u003e pocket is machined into the panel opposite the baffle, directly behind the magnet. It buys motor clearance for a 6.65 inch deep driver without adding cabinet height.\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\u003eJL Audio rates the 12W3v3-4 at \u003cstrong\u003e500 watts RMS continuous\u003c\/strong\u003e and recommends 150 to 500 watts of amplifier power. At 87.15 dB sensitivity this driver produces solid output even in the middle of that range. It is a single voice coil at 4 ohms nominal, so there is no series or parallel decision to make: one side mounted cup, and the amplifier sees 4 ohms.\u003c\/p\u003e\n\u003cp\u003eThe enclosure carries a 1 year limited warranty. Bring your own JL Audio 12W3v3-4; 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\u003eCutout, internal height and magnet relief are machined for this one driver, then built one at a time in Tullahoma, Tennessee.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Proline X","offers":[{"title":"Default Title","offer_id":44540827598937,"sku":"PO 12-S DF W3","price":249.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0689\/1389\/files\/proline-x-micro-series-dual-15-sealed-enclosure-built-for-resonix-gus-15subwoofer-enclosuresproline-x-9360178_38c79609-01f9-48f2-add3-2f862004c930.jpg?v=1787118621","url":"https:\/\/audiointensity.com\/products\/performance-optimized-down-fire-sealed-12-enclosure-jl-audio-12w3v3-4","provider":"Audio Intensity","version":"1.0","type":"link"}