{"product_id":"rcf-lf21n451-21-1500w-8-ohm-speaker-driver-woofer","title":"RCF LF21N451 - 21\" 1500W 8 Ohm Speaker Driver Woofer","description":"\u003cp data-start=\"0\" data-end=\"12\"\u003eDescription:\u003c\/p\u003e \u003cp data-start=\"0\" data-end=\"12\"\u003ePlease note this is for one driver, image shows front and back.\u003c\/p\u003e \u003cp data-start=\"14\" data-end=\"343\"\u003eThe LF21N451 is a high-power 21\" low-frequency transducer engineered for demanding subwoofer applications requiring extreme output, efficiency, and precision. Designed to deliver powerful and accurate sub-bass performance, it is ideal for large-scale sound reinforcement systems, touring rigs, and high-performance installations.\u003c\/p\u003e \u003cp data-start=\"345\" data-end=\"820\"\u003eAt the heart of the driver is a 4.5\" inside\/outside copper voice coil, optimised for high excursion and improved linearity at very low frequencies. The cone is constructed from an advanced carbon fibre, nylon, and cellulose composite, providing exceptional rigidity and resistance to deformation under high pressure. Combined with a triple-roll surround and dual spider system with silicon-based damping, the driver maintains precise control even at extreme excursion levels.\u003c\/p\u003e \u003cp data-start=\"822\" data-end=\"1174\"\u003eThe LF21N451 also features a dual-forced air ventilation system to minimise power compression and ensure efficient cooling during high-output operation. A neodymium magnet structure and optimised T-pole design contribute to improved efficiency and reduced flux modulation, resulting in fast, accurate low-frequency reproduction with minimal distortion.\u003c\/p\u003e \u003cp data-start=\"1176\" data-end=\"1185\"\u003eFeatures:\u003c\/p\u003e \u003cp data-start=\"1187\" data-end=\"1226\"\u003eType: 21\" High-Power Subwoofer Driver\u003c\/p\u003e \u003cp data-start=\"1228\" data-end=\"1294\"\u003ePower Handling: 1500W RMS \/ 3000W Program\u003cbr data-start=\"1269\" data-end=\"1272\"\u003eSensitivity: 98.5 dB\u003c\/p\u003e \u003cp data-start=\"1296\" data-end=\"1408\"\u003eVoice Coil: 4.5\" Copper Voice Coil (Inside\/Outside Winding)\u003cbr data-start=\"1355\" data-end=\"1358\"\u003eCone: Carbon Fibre \/ Nylon \/ Cellulose Composite\u003c\/p\u003e \u003cp data-start=\"1410\" data-end=\"1502\"\u003eSurround: Triple-Roll Polycotton Surround\u003cbr data-start=\"1451\" data-end=\"1454\"\u003eDesign: Dual Spider with Silicon-Based Damping\u003c\/p\u003e \u003cp data-start=\"1504\" data-end=\"1562\"\u003eCooling: Dual-Forced Air Ventilation\u003cbr data-start=\"1540\" data-end=\"1543\"\u003eMagnet: Neodymium\u003c\/p\u003e \u003cp data-start=\"1564\" data-end=\"1676\"\u003ePerformance: High Excursion Design with Low Distortion\u003cbr data-start=\"1618\" data-end=\"1621\"\u003eBL Factor: 34.5 Tm for Fast, Accurate Low Frequencies\u003c\/p\u003e \u003cp data-start=\"1678\" data-end=\"1757\"\u003eApplication: High-performance subwoofers, touring systems, and large-scale PA\u003c\/p\u003e \u003cp data-start=\"1759\" data-end=\"1774\"\u003eSpecifications:\u003c\/p\u003e \u003cp data-start=\"1776\" data-end=\"1849\"\u003eNominal Diameter: 21\" (533mm)\u003cbr data-start=\"1805\" data-end=\"1808\"\u003eImpedance: 8Ω\u003cbr data-start=\"1821\" data-end=\"1824\"\u003eMinimum Impedance: 7.1Ω\u003c\/p\u003e \u003cp data-start=\"1851\" data-end=\"1919\"\u003eFrequency Response: 30Hz – 1000Hz\u003cbr data-start=\"1884\" data-end=\"1887\"\u003eResonance Frequency (Fs): 30Hz\u003c\/p\u003e \u003cp data-start=\"1921\" data-end=\"1975\"\u003eVoice Coil Diameter: 114mm\u003cbr data-start=\"1947\" data-end=\"1950\"\u003eVoice Coil Length: 34mm\u003c\/p\u003e \u003cp data-start=\"1977\" data-end=\"2021\"\u003eSensitivity: 98.5 dB\u003cbr data-start=\"1997\" data-end=\"2000\"\u003eBL Factor: 34.50 Tm\u003c\/p\u003e \u003cp data-start=\"2023\" data-end=\"2072\"\u003eXmax: 13mm\u003cbr data-start=\"2033\" data-end=\"2036\"\u003eMax Excursion (Peak-to-Peak): 58mm\u003c\/p\u003e \u003cp data-start=\"2074\" data-end=\"2147\"\u003eEffective Piston Diameter: 470mm\u003cbr data-start=\"2106\" data-end=\"2109\"\u003eEffective Piston Area (Sd): 0.170 m²\u003c\/p\u003e \u003cp data-start=\"2149\" data-end=\"2222\"\u003eMounting Diameter: 547mm\u003cbr data-start=\"2173\" data-end=\"2176\"\u003eBolt Circle Diameter: 527mm\u003cbr data-start=\"2203\" data-end=\"2206\"\u003eCut-Out: 512mm\u003c\/p\u003e \u003cp data-start=\"2224\" data-end=\"2255\"\u003eDepth: 249mm\u003cbr data-start=\"2236\" data-end=\"2239\"\u003eWeight: 10.9kg\u003c\/p\u003e \u003cp data-start=\"2257\" data-end=\"2313\"\u003eMagnet Type: Neodymium\u003cbr data-start=\"2279\" data-end=\"2282\"\u003eSurround Material: Polycotton\u003c\/p\u003e \u003cp data-start=\"2315\" data-end=\"2329\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eCompliance: CE\u003c\/p\u003e","brand":"RCF","offers":[{"title":"Default Title","offer_id":51889067852096,"sku":"150-11100043","price":599.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0784\/9322\/1184\/files\/f7d295f0-ad43-45fc-a550-c42f00801d1f.jpg?v=1777270921","url":"https:\/\/www.simplysoundandlighting.co.uk\/products\/rcf-lf21n451-21-1500w-8-ohm-speaker-driver-woofer","provider":"Simply Sound and Lighting","version":"1.0","type":"link"}