{"product_id":"professional-series-ported-15-enclosure-sundown-audio-u-series-v-1-15","title":"Professional Series Ported 15\" Enclosure | Sundown Audio U-Series v.1 15","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%,#001a91 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(91,120,255,.18);border:1px solid #5b78ff;color:#99abff;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\n\u003cdiv class=\"df-hero\"\u003e\n  \u003ch2\u003eProline X Professional 15\" Ported\u003c\/h2\u003e\n  \u003cp\u003eA ported fifteen-inch box built for the U-Series v.1 15, tuned flat and shared by both coil options\u003c\/p\u003e\n  \u003cdiv class=\"df-badges\"\u003e\n    \u003cspan class=\"df-badge\"\u003e2.52 cu ft net\u003c\/span\u003e\n    \u003cspan class=\"df-badge\"\u003eTuned 34.0 Hz\u003c\/span\u003e\n    \u003cspan class=\"df-badge\"\u003eF3 31.6 Hz\u003c\/span\u003e\n    \u003cspan class=\"df-badge\"\u003e2.25\" three-layer baffle\u003c\/span\u003e\n    \u003cspan class=\"df-badge\"\u003eCut for the U-Series v.1 15\u003c\/span\u003e\n    \u003cspan class=\"df-badge\"\u003eBuilt in Tennessee\u003c\/span\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"df-stats\"\u003e\n  \u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e2.52\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\"\u003e34.0\u003c\/span\u003e\u003cspan class=\"l\"\u003eHz tuning\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e31.6\u003c\/span\u003e\u003cspan class=\"l\"\u003eHz F3 anechoic\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003cdiv class=\"df-stat\"\u003e\n\u003cspan class=\"n\"\u003e49.5\u003c\/span\u003e\u003cspan class=\"l\"\u003esq in port area\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"df-section\"\u003e\n  \u003ch3\u003eWhy this driver is vented at 34.0 Hz\u003c\/h3\u003e\n  \u003cp\u003eThe Sundown Audio U-Series v.1 15 is a shallow driver at 9.05 inches deep, and this cabinet holds it in 2.525 cubic feet net, vented at 34.0 Hz through a 49.5 square inch port. F3 lands at 31.6 Hz with just 0.16 dB of passband ripple, the flattest response of any Professional pick in this size class. At 36 inches wide, 18 inches tall and 15.0 inches deep, it is the shallow-mount fifteen inch envelope.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eThreaded insert kit ships with this box.\u003c\/strong\u003e Sundown Audio does not publish the mounting hole locations for the U-Series v.1 15, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer; one kit serves one woofer.\u003c\/p\u003e\n  \u003cp\u003eAt the coil's rated power of 1500 W the port on this box is nowhere near the chuff line; it stays clean all the way to 2091 W before the mouth velocity crosses it, so the coil's own heat is the limit here, not the port. Sundown publish a Qts of 0.31 for the D2 coil, with the Qes and Qms behind it in close agreement, describing a driver damped enough to sit flat rather than peak anywhere in the passband. Ripple across the passband holds at 0.16 dB, essentially flat, and the in-car curve stays close to that same line.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"df-section\"\u003e\n  \u003ch3\u003eWhat makes it Professional\u003c\/h3\u003e\n  \u003cdiv class=\"df-grid\"\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eThree-layer baffle, flush mount\u003c\/h4\u003e\n\u003cp\u003eThree layers of 3\/4 inch Langboard Elite make a 2.25 inch\n    front. The outer layer is routed to the flange, so the woofer sits flush with the face; the two layers behind it\n    carry the mounting hardware and the load.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eSundown Audio logo acrylic\u003c\/h4\u003e\n\u003cp\u003eA glossy black acrylic insert with the Sundown Audio mark sits in the outer\n    layer beside the woofer. It is standard on every Professional cabinet.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eThreaded insert kit ships with this box\u003c\/h4\u003e\n\u003cp\u003eThreaded insert kit included, inserts NOT pre-installed: the manufacturer publishes no mounting hole locations, so the kit ships with the box for installation when the woofer goes in: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, allen key and gasket tape.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003ePort gated at 1500 W\u003c\/h4\u003e\n\u003cp\u003eThe 49.5 square inch slot beside the woofer is sized so the\n    channel runs 20.4 metres per second and the mouth 14.4 metres per second at the driver's rated power, under the\n    17 metres per second where a slot starts to chuff. The channel runs 8.25 inches along its wall and turns once along the back wall for another 19.84 inches, which is why a 34.0 Hz tuning fits a 15.00 inch deep box.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eWhy this is a Professional build\u003c\/h4\u003e\n\u003cp\u003eEvery driver is run through the Performance Optimized wedge and down-fire before this chassis; the Professional box is where a driver lands when that smaller envelope, 30 inches wide and 18 inches deep with a triangular side port, cannot give it what it needs at its rated power. The U-Series v.1 15 did not clear the port gate there. The calmest wedge port that fits that envelope is 32.0 square inches at 26.0 by 11.12 by 17.86 inches, and its mouth runs 20.3 metres per second at 1500 W against the 17 metres per second line where a port starts to chuff. That port would stay clean to about 1054 W. The slot on this box reaches 49.5 square inches and holds the mouth at 14.4 metres per second at 1500 W.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eWhat the price covers\u003c\/h4\u003e\n\u003cp\u003eEvery Professional cabinet is priced the same way, by its size: this one is 5.62 cubic feet outside. Delivery to the 48 states is inside the price; it ships as a 84 lb parcel and checkout adds nothing. The Performance Optimized 15 inch ported wedge is $499.99. The $90 difference is the larger box and the port this driver needs to run at its rating.\u003c\/p\u003e\n\u003c\/div\u003e\n    \u003cdiv class=\"df-card\"\u003e\n\u003ch4\u003eWhat Sundown Audio recommend\u003c\/h4\u003e\n\u003cp\u003eSundown Audio publish a vented box for the U-Series v.1 15 at 3.00 cubic feet on a basis they do not state, tuned to 35.0 Hz. This cabinet holds 2.52 cubic feet net and tunes to 34.0 Hz. They call for a port area of 48 sq in. The chassis envelope sets the volume here, and the port is sized so the mouth stays under the chuff threshold at the design power rather than to reach their figure.\u003c\/p\u003e\n\u003c\/div\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"df-section\"\u003e\n  \u003ch3\u003eThe cabinet\u003c\/h3\u003e\n  \u003cp\u003e36.00\" W x 18.00\" H x 15.00\" D external. Two windowed braces run front to back either side of the woofer, clearing the cutout by two and a half inches. The box ships dry: polyfill detunes a ported alignment. This is our single fifteen inch Professional envelope built for the U-Series v.1 15's shallow mount, shared by the D2 and D4 coils. It ships as a parcel.\u003c\/p\u003e\n  \u003cp\u003eSundown publish per-coil T\/S for the U-Series v.1 15, and the D2 column is what this cabinet is built to; the D4 winding shares the same basket and frame and fits this same cabinet. Nothing about this driver's numbers needed a workaround or an estimate. Sundown Audio does not publish the mounting hole locations for the U-Series v.1 15, so we cannot install the threaded inserts before it ships. The threaded insert kit comes in the box instead: 8 to 12 inserts sized to the woofer, the correct drill bit, 2.5 inch allen-head screws, an allen key and woofer gasket tape. You set the inserts when you mount the woofer; one kit serves one woofer.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"df-section\"\u003e\n  \u003ch3\u003eThe numbers to respect\u003c\/h3\u003e\n  \n  \u003cp\u003eSet a 27 Hz subsonic filter, 24 dB per octave. Below tuning the vent stops loading the cone; with the filter in\n  place the cone reaches 8.0 mm of its 30.0 mm at 1500 W.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e","brand":"Proline X","offers":[{"title":"Default Title","offer_id":44853116567641,"sku":"Pro 15-P U15","price":589.99,"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_d2c17724-8fa0-48a2-84ea-7d9cb3409b00.jpg?v=1788802193","url":"https:\/\/audiointensity.com\/products\/professional-series-ported-15-enclosure-sundown-audio-u-series-v-1-15","provider":"Audio Intensity","version":"1.0","type":"link"}