RDL RU-PA40D – 40 W Stereo Amplifier with VCA Control

What is the RDL RU-PA40D?The RDL RU-PA40D is a 40 W stereo Class D amplifier with an internal VCA, delivering 20 W RMS per channel into 8 Ω or 15 W per channel into 4 Ω. Users can adjust level through RDL remote controls, a 10 kΩ potentiometer or a 0 to 10 Vdc control voltage. It suits classrooms, boardrooms, video conferencing rooms and retail zones, and includes its power supply with a North American cord.How does it work?The RU-PA40D drives a pair of 4 Ω or 8 Ω speakers, with output impedance selected on the front panel. Balanced line inputs connect on a detachable terminal block, and unbalanced inputs use gold-plated RCA jacks. Front-panel trimmers set the maximum gain for each channel across typical balanced and unbalanced levels. The internal stereo VCA sets output level on both channels from an external 10 kΩ potentiometer or 0 to 10 Vdc, with a 10 Vdc reference provided. RDL remote controls such as the RDL D-RLC10 provide single-turn, rotary encoder or pushbutton level control over audio, control or network cable. A front-panel switch sums the inputs to mono when speaker placement does not suit stereo. The stereo analog compressor/limiter prevents clipping and, with higher input gain, raises average output beyond a standard 40 W amplifier. A red THRESHOLD LED flashes when the limiter is active, and a blue LED shows power. The included supply accepts 100 to 240 Vac and powers the module at 24 Vdc; the amplifier has thermal and output short-circuit protection. It mounts with RDL RACK-UP accessories such as the RDL RU-HRA1 or RDL RC-1UR.What are the key features? 40 W stereo Class D — 20 W RMS per channel into 8 Ω or 15 W per channel into 4 Ω. Internal VCA — Remote level control by 10 kΩ potentiometer, 0 to 10 Vdc or RDL controls. Balanced and unbalanced inputs — Terminal block and gold-plated RCA connections. Stereo or summed mono — Front-panel switch adapts to the speaker layout. Compressor/limiter — Prevents clipping and maximizes average output power. Supply included — 100 to 240 Vac supply with North American cord. Where is it typically used? Conference room Boardroom Training room Huddle room Commercial meeting space Technical Specifications Model RU-PA40D Crosstalk Better than 60 dB (1 kHz, no compression) Compressor Threshold nominally 2 dB below rated output, automatically adjusting attack and release times THD+N < 0.1% (1 kHz, 1 W, 4 or 8 Ohms); < 1% (50 Hz to 20 kHz,)* *measured at compressor threshold level equaling 12 W RMS (8 Ohms) output power VCA Control External 0 to 10 Vdc (linear), 10 kΩ linear taper potentiometer, RDL remote controls; 10 Vdc VCA reference voltage output provided Frequency Response 20 Hz to 20 kHz (± 1 dB, 4 or 8 Ohms)* Maximum Input Levels +22 dBu balanced, +12 dBV unbalanced Gain Adjustments (2) Single turn, one per channel Minimum Input Levels -11 dBu balanced, -18 dBV unbalanced (to cross compressor threshold) Input Impedance 50 kΩ balanced, 20 kΩ unbalanced Inputs (4) Line level: Balanced (+4 dBu) Left and Right, Unbalanced (-10 dBV) Left and Right Noise (below 20 W RMS) < -80 dB (VCA control 6.25V; output level 6 dB below max.) < -70 dB (VCA control max.) Selectors (2) Slide switches: Output Impedance 4 Ohms or 8 Ohms; Input Mode SUMMED MONO or STEREO Output Power 20 W RMS into 8 Ω per channel, 40 W RMS total; 15 W RMS into 4 Ω per channel, 30 W RMS total Output Circuit Class D Ambient Operating Environment 32° F to 104° F (0° C to 40° C) Maximum; 68° F (20° C) recommended Indicators (2) Red LED: THRESHOLD LED indicates compressor activity; Blue LED: POWER on Power Supply (included) 100 to 240 Vac, 50-60 Hz, 1.5A; 24 Vdc output to module Frequently Asked QuestionsWhat power does it deliver?20 W RMS per channel into 8 Ω (40 W total) or 15 W RMS per channel into 4 Ω (30 W total).How can users control volume?Through the internal VCA using an external 10 kΩ potentiometer, 0 to 10 Vdc, or RDL remote level controls.Can it run in mono?Yes. A front-panel switch sums the inputs to mono.Is a power supply included?Yes. The supply accepts 100 to 240 Vac and includes a North American cord. The RU-PA40DE export model excludes the cord.What inputs does it have?Balanced +4 dBu inputs on a terminal block and unbalanced -10 dBV inputs on RCA jacks.What warranty does it carry?This 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.Can Creation Networks help design the system?Yes. Our team specifies, programs and installs classroom and conference room audio systems for commercial projects nationwide. Call (888) 230-3661 for a quote or design review.