Yorkville power amp 4020 The powerful AP4020/AP4040 weigh a comfortable but solid 40/43 lbs. and occupy only two rack spaces. They deliver 1200 Watts per channel (AP4020 @ 2 Ohms, AP4040 @ 4 Ohms). The AP4020/4040 power amplifiers also incorporate a 'soft turn-on' circuit which eliminates nuisance breaker-tripping on power-up.AudioPro amplifiers feature advanced protection schemes including DC current, load, thermal and breaker protection as well as a user-defeatable peak limiter that is transparent below clipping levels. A 'soft turn-on' circuit eliminates damage to attached components and prevents nuisance breaker-tripping. The computer-optimized (Silentfan) front-to-back heat dissipation system incorporates ultra-quiet, variable-speed internal fans and are designed to ensure that excessive thermal stress will not occur. For ease of maintenance and to ensure efficient cooling, the amplifiers are supplied with long-life, faceplate-mounted, user serviceable, air intake filters. Front panel Power, Protect, Activity and Clip LED's are bright and easy to see and all knobs and handles are recessed for safe, easy transportation.The internal signal path has been optimized and a toroidal transformer is used - both of which serve to reduce hum and noise while keeping weight to a minimum. The two-tier power conversion of the AudioPro AP-Series amplifiers approaches efficiency levels normally associated with switching power supply technology; yet provide the superior transient response and low distortion of the best analog designs. Inside an AP4020 AudioPro amplifier designs, while unique, are conservative with regard to the power handling capabilities of the output devices. To further assure trouble-free operation, all AudioPro amplifiers undergo a thorough computer-monitored, temperature-cycled, burn-in period to test for any deviation from design parameters.The back panel features Speakon and binding post outputs as well as balanced XLR & 1/4" TRS inputs. The peak limiter, subsonic filter, mono/stereo/bridge mode and ground lift switches are also mounted on the back panel. The unique Yorkville Impedance Mode switch (AP1020 & AP2020), also located on the back panel, allows the user to select full output power into two or four ohms for maximum application flexibility.Features:• Delivers 1200 watts per channel at 2 ohms• (2400 watts bridged into 4 ohms)• Proven Ultra Reliable Conventional Designs• Easily Handles Reactive Phase Shifted Loads• Advanced Protection Schemes Including DC Current, Load, Thermal & Breaker Protection• Transparent User-Defeatable Peak Limiter Circuits• Soft Turn-On Circuit Protects Speakers and Prevents Nuisance Breaker Tripping During Power Up• Computer-Optimized Silentfan Front-to-Back Heat Dissipation System• Long-Life, Faceplate-Mounted, User Serviceable, Air Intake Filters• Front Panel Power, Protect, Activity and Clip Led's• Speakon and Binding Post Outputs• Balanced XLR and -inch TRS Inputs• All-Steel Chassis ConstructionSpecifications:• Amplifier class: H• Continuous Average Power @ 8 Ohms BCD (Watts): 475 (x2)• Continuous Average Power @ 4 Ohms BCD (Watts): 750 (x2)• Continuous Average Power @ 2 Ohms BCD (Watts): 1200 (x2)• Continuous Average Power Bridged BCD (Watts): 2400 @ 4 Ohms• Burst Average Power @ 8 Ohms BCD(Watts): 625 (x2)• Burst Average Power @ 4 Ohms BCD (Watts): 1200 (x2)• Burst Average Power @ 2 Ohms BCD (Watts): 2175 (x2)• Burst Average Power Bridged BCD (Watts): 4350 @ 4 Ohms• Frequency Response (Hz, +/- 1dB): 20-20,000• Hum and Noise (un / Aweighted -dB): 0.971698113207547• THD -1kHz- 4 OHMS: 0.0001• THD - 20Hz-20kHz, 4 Ohms: less than 0.1%• Slew Rate (V/uS): 25• Slew Rate Bridged (V/uS): 50• Damping Factor (30 Hz - 400 Hz @ 8 Ohms): 600• Crosstalk (1kHz / 20Hz-20kHz): -75 / -60 dB• Input Impedance - Bal/Unbal (Ohms): 20,000/10,000• Input Sensitivity (Vrms) For Full Power Out: 1.4 V• Max Voltage Gain (dB): 33• CMRR @ 60Hz (min/typ):48/56 dB• Stereo / Mono / Bridge )S/M/B): S/M/B• Protection: DC,Load,Thermal• Limiter: Peak• High Pass Filter: 40Hz, 12dB Octave• Cooling: Internal Fan• Cooling Path: Front to Rear• Fan Filter: User Serviceable• Inputs - XLR: 2• Inputs - 1/4 IN Jacks: 2• Outputs - Speakon 4-pin: 2• Outputs - Binding Post: 2• Power Consumption (typ/max): 1130/1800 Watts• Rack Spaces: 2• Transformer Type: Toroidal• Exterior Finish: Baked, Black Painted• Dimensions (DWH /D fm ears, inches): 19 x 17.3 x 3.5 x 16.2• Dimensions (DWH /D fm ears, cm): 48.3 x 43.9 x 8.9 x 41