{"product_id":"rdl-sf-pa50a","title":"RDL SF-PA50A – 50 W Mono Amplifier, 70\/100 V, Plenum Rated","description":"\u003ch2\u003eWhat is the RDL SF-PA50A?\u003c\/h2\u003e\u003cp\u003eThe RDL SF-PA50A is a 50 W RMS Class D power amplifier that drives 70 V or 100 V constant voltage speaker lines from a single analog input. It is plenum rated per UL 2043, so it can be installed above ceilings in air-handling spaces. Remote VCA level control and power supply protection make it a dependable amplifier for distributed paging and background music.\u003c\/p\u003e\u003ch2\u003eHow does it work?\u003c\/h2\u003e\u003cp\u003e\u003cimg src=\"https:\/\/rdlnet.com\/wp-content\/uploads\/2024\/01\/sf-pa50a.jpg\" alt=\"RDL SF-PA50A 50 W Mono Amplifier, 70\/100 V, Plenum Rated\" style=\"max-width:100%;height:auto\" loading=\"lazy\"\u003e\u003c\/p\u003e\u003cp\u003eAn analog source connects to either the balanced mono terminal block input or the unbalanced stereo mini-jack, which sums left and right to mono. The installer sets gain with a rear-panel single-turn control and a dual-LED VU meter calibrated to 20 dB below full output power. An internal VCA sets the output level from an external 10 kΩ potentiometer, a 0 to 10 Vdc control voltage or RDL remote level controls, providing long-term noise-free adjustment. The high-efficiency Class D stage produces minimal heat, and thermal and output short-circuit protection are built in. During power-up, overload or overheating, a yellow MUTE LED lights and the output mutes. The amplifier monitors its power draw and limits current so the included 24 Vdc supply does not shut down, even under extreme feedback or square wave conditions, and a red OVERLOAD PROTECT LED flashes when this occurs. Frequency response is 50 Hz to 20 kHz (+0\/-3 dB). The all-metal SYSFLEX enclosure supports free-standing, surface-mounted or rack-mounted operation, and the \u003ca href=\"https:\/\/creationnetworks.net\/products\/rdl-sf-ucb2\"\u003eSF-UCB2 under counter bracket pair\u003c\/a\u003e mounts it beneath a counter or table. RDL engineers and manufactures the SF-PA50A in the USA for continuous duty in demanding installations.\u003c\/p\u003e\u003ch2\u003eWhat are the key features?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e50 W RMS at 70 V or 100 V\u003c\/strong\u003e — Drives distributed constant voltage speaker lines from one compact unit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlenum rated per UL 2043\u003c\/strong\u003e — Approved for installation in air-handling spaces above ceilings.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBalanced or mini-jack input\u003c\/strong\u003e — Connect a balanced mono source or a stereo device summed to mono.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRemote VCA level control\u003c\/strong\u003e — Use a 10 kΩ potentiometer, 0 to 10 Vdc or RDL remote controls.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower supply protection\u003c\/strong\u003e — Current limiting prevents supply shutdown during extreme feedback.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClass D with full protection\u003c\/strong\u003e — Efficient operation with thermal and short-circuit protection.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhere is it typically used?\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eConference room\u003c\/li\u003e\n\u003cli\u003eTraining room\u003c\/li\u003e\n\u003cli\u003eMulti-purpose room\u003c\/li\u003e\n\u003cli\u003eCommercial meeting space\u003c\/li\u003e\n\u003cli\u003eGovernment space\u003c\/li\u003e\n\u003cli\u003eHouse of worship\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003cdiv style=\"overflow-x:auto;-webkit-overflow-scrolling:touch\"\u003e\u003ctable style=\"border-collapse:collapse;width:100%;min-width:300px;table-layout:fixed\"\u003e\n\u003ccolgroup\u003e\n\u003ccol style=\"width:44%\"\u003e\n\u003ccol style=\"width:56%\"\u003e\n\u003c\/colgroup\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eAnalog inputs (2)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eBalanced terminal block or stereo unbalanced mini-jack (summed to mono)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eBalanced input level\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e+4 dBu nominal; -10 dBu minimum; +25 dBu maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eUnbalanced input level\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e-10 dBV nominal; -25 dBV minimum; +10 dBV maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eInput impedance\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e\u0026gt; 10 kΩ balanced; \u0026gt; 5 kΩ unbalanced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eCommon mode rejection\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e\u0026gt; 60 dB (50 Hz to 120 Hz)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eAmplifier output\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e50 W RMS (70 V or 100 V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eFrequency response\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e+0\/-3 dB (50 Hz to 20 kHz)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eIndicators (5)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003ePower (blue), Amplifier muted (yellow), Overload Protect (red), dual-LED VU meter (2)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eVCA\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e0 to 10 Vdc control, detachable terminal block\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003ePower requirement\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e24 Vdc @ 2700 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003ePower supply (included)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e100 to 240 Vac, 50-60 Hz, IEC C14 inlet; 24 Vdc output\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003ePlenum rating\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003eUL 2043\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eOperating environment\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e32°F to 104°F (0°C to 40°C) maximum; 68°F (20°C) recommended\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e1.7 x 5.83 x 6.45 in (4.32 x 14.8 x 16.38 cm) H x W x D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px;vertical-align:top\"\u003e\u003cstrong\u003eShipping weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #ddd;padding:6px\"\u003e4.22 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eCan the SF-PA50A be installed above a ceiling?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. It is plenum rated per the UL 2043 standard.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eWhich speaker line voltages does it support?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eIt delivers 50 W RMS at 70 V or 100 V constant voltage.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eIs the power supply included?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. An external 100 to 240 Vac supply with 24 Vdc output is included.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eCan I control volume from a wall plate?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. The VCA accepts a 10 kΩ potentiometer, a 0 to 10 Vdc control or RDL remote level controls.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eCan I connect a phone or laptop directly?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eYes. The stereo mini-jack input sums left and right to mono.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003e\u003cstrong\u003eWhat warranty applies?\u003c\/strong\u003e\u003c\/summary\u003e\u003cp\u003eThis product is covered by a 7-year RDL warranty. For warranty claims, RMAs or support, contact Creation Networks at (888) 230-3661 or sales@creationnetworks.net.\u003c\/p\u003e\u003c\/details\u003e","brand":"RDL","offers":[{"title":"Default Title","offer_id":68025793773804,"sku":"SF-PA50A","price":398.33,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0603\/7982\/4364\/files\/sf-pa50a.jpg?v=1793583898","url":"https:\/\/creationnetworks.net\/products\/rdl-sf-pa50a","provider":"Creation Networks","version":"1.0","type":"link"}