{"product_id":"performance-optimized-down-fire-sealed-11-enclosure-stereo-integrity-bm-11","title":"Performance Optimized Down Fire Sealed 11\" Enclosure | Stereo Integrity BM-11","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 11\" Sealed\u003c\/h2\u003e\n\u003cp\u003eCut and tuned for the Stereo Integrity BM-11\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\"\u003e0.40 cu ft Net\u003c\/span\u003e\u003cspan class=\"df-badge\"\u003eStandoffs Included\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\"\u003e0.40\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\"\u003e1.26 to 1.43\u003c\/span\u003e\u003cspan class=\"l\"\u003esystem Qtc across published data\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e41.1 to 42.6 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\"\u003e5.00 in\u003c\/span\u003e\u003cspan class=\"l\"\u003ecabinet height, excludes standoffs\u003c\/span\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\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.\u003c\/td\u003e\n\u003ctd class=\"on\"\u003eA shared 30 by 15 inch platform on most builds, with cabinet height as the variable. This build is an exception and runs narrower, because the BM-11's airspace is small enough that the standard width would overshoot it.\u003c\/td\u003e\n\u003ctd\u003eCompact per driver footprint.\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, 1.5 inch, outer layer machined as a flush recess.\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\"\u003eThreaded inserts, stainless machine screws included.\u003c\/td\u003e\n\u003ctd\u003eThreaded 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\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 BM-11's own 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 Stereo Integrity BM-11\u003c\/h3\u003e\n\u003cp\u003eNothing about this cabinet is generic. The baffle is bored to the BM-11's \u003cstrong\u003e254 mm cutout\u003c\/strong\u003e, the internal height is set by its \u003cstrong\u003e3.071 inch mounting depth\u003c\/strong\u003e, and the airspace lands on \u003cstrong\u003e0.40 cubic feet net\u003c\/strong\u003e, the volume Stereo Integrity names as the middle of their recommended range.\u003c\/p\u003e\n\u003cp\u003eThe BM-11 is a shallow mount 11 inch on a 283 mm frame, 500 watts RMS, with 13 mm of one-way linear excursion quoted at the 70 percent BL threshold and a sensitivity of 82.5 dB at 1 W. It is a heavy cone on a compliant suspension, which is what produces its high total Q and is the reason it wants a small sealed box rather than a large one.\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\u003e0.40 cubic feet net\u003c\/strong\u003e. The volume quoted is true net internal airspace after panel thickness, bracing and the driver's own 0.03 cubic feet of displacement are accounted for. Gross is 0.4371.\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\u003eWidth was solved to hit 0.40 exactly rather than rounded to a stock platform, which is why this cabinet is 22.84 inches wide instead of the 30 inch shared footprint most Performance Optimized down fire builds use.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eWhat the Alignment Actually Is\u003c\/h3\u003e\n\u003cp\u003eThis is a high Q driver and this is a small box, so the result is a peaked alignment rather than a flat one. That is not a compromise in the build, it is what the BM-11 is designed to do. Stereo Integrity recommends 0.30 to 0.75 cubic feet and names 0.40 as the figure to build to, and that is what this cabinet delivers.\u003c\/p\u003e\n\u003cp\u003eThree independent parameter sets exist for this driver and they do not fully agree, so all three are given rather than the most flattering one.\u003c\/p\u003e\n\u003ctable class=\"df-tier\"\u003e\n\u003ctr\u003e\n\u003cth\u003eParameter source\u003c\/th\u003e\n\u003cth\u003eSystem Qtc\u003c\/th\u003e\n\u003cth\u003efc\u003c\/th\u003e\n\u003cth\u003eF3\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStereo Integrity, published\u003c\/td\u003e\n\u003ctd\u003eQtc 1.265\u003c\/td\u003e\n\u003ctd\u003e58.7 Hz\u003c\/td\u003e\n\u003ctd\u003e42.6 Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eloudspeakerdatabase\u003c\/td\u003e\n\u003ctd\u003eQtc 1.432\u003c\/td\u003e\n\u003ctd\u003e58.8 Hz\u003c\/td\u003e\n\u003ctd\u003e41.5 Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResoNix, Klippel measured\u003c\/td\u003e\n\u003ctd\u003eQtc 1.363\u003c\/td\u003e\n\u003ctd\u003e57.6 Hz\u003c\/td\u003e\n\u003ctd\u003e41.1 Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003cdiv class=\"df-note\"\u003e\u003cp\u003e\u003cstrong\u003eRead the range, not one number.\u003c\/strong\u003e System Qtc lands between 1.26 and 1.43 depending on whose parameters you use, and F3 between 41.1 and 42.6 Hz. A sealed box cannot produce a Qtc below the driver's own Qts no matter how large it is, and on this driver that floor is already above the textbook targets. Anyone quoting you a 0.707 alignment on a BM-11 is quoting a box that cannot exist.\u003c\/p\u003e\u003c\/div\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. 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\u003e22.84 inches wide by 15.00 inches deep by 5.00 inches tall, measured in the down fire position and excluding standoffs\u003c\/strong\u003e. Plan the space around the installed height rather than the cabinet height: the standoffs hold 1.75 inches under the baffle, so the finished stack sits near \u003cstrong\u003e6.75 inches\u003c\/strong\u003e.\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.\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\u003eStandoffs Included\u003c\/h4\u003e\n\u003cp\u003eStereo Integrity publishes no front clearance figure for the BM-11, so this cabinet uses the Proline X standard \u003cstrong\u003e1.75 inch\u003c\/strong\u003e standoff, shipped with every enclosure and left uninstalled so you can place them to suit your floor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003eMotor Clearance and Orientation\u003c\/h3\u003e\n\u003cp\u003eThe motor rises off the baffle into the cavity, so on a down fire cabinet the clearance that matters runs to the top panel. At the 5.00 inch cabinet height there is \u003cstrong\u003e1.179 inches above the motor\u003c\/strong\u003e, against a 0.75 inch minimum. Height was set to 5.00 rather than the 4.57 the volume alone would have allowed, specifically to keep that margin.\u003c\/p\u003e\n\u003cp\u003eStereo Integrity does not publish a position on down firing this driver, and this cabinet makes no claim on their behalf. The feet ship uninstalled, so if you would rather run it front firing or up firing, that is a decision you can make at install time without changing anything about the enclosure.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"df-section\"\u003e\n\u003ch3\u003ePower and Warranty\u003c\/h3\u003e\n\u003cp\u003eThe BM-11 is rated \u003cstrong\u003e500 watts RMS\u003c\/strong\u003e with a dual 2 ohm voice coil, which gives 4 ohms in series or 1 ohm in parallel. The 1 ohm load is one many amplifiers are not stable into, so series is the safe default unless your amplifier is explicitly rated for it.\u003c\/p\u003e\n\u003cp\u003eThe enclosure carries a 1 year limited warranty. Bring your own BM-11; 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\u003eBuilt one at a time in Tullahoma, Tennessee, with standoffs and a 1 year limited warranty. Questions on fitment or amplifier matching, call or text 931-563-5151.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Proline X","offers":[{"title":"Default Title","offer_id":44589818151001,"sku":"PO 11-S DF BM11","price":239.99,"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_c7af6f19-5969-4cc3-a2f3-3cf1ff4a7ade.jpg?v=1787973527","url":"https:\/\/audiointensity.com\/products\/performance-optimized-down-fire-sealed-11-enclosure-stereo-integrity-bm-11","provider":"Audio Intensity","version":"1.0","type":"link"}