QSC mx 1500 mx 2000 Service Manual

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TABLE OF CONTENTS MX1500 Specifications ........................................................................\ ............................................... 3 MX1500 Printed Circlrit Layotit & Parts List ........................................................................\ ............... 4 ........................................................................\ ................................... h4X2500 Component Plac6merit 5 ........................................................................\ ............... MX 1 500 Ckaiinel Module Assembly Details -6 ........................................................................\ .................................................... MX 1500 Schematic 7 ........................................................................\ ................... MX1 500 Primary Wiring Information ., .... 8 ........................................................................\ .................................... MX1500 Chassis Disassembly 9 ........................................................................\ ............................................. MX2000 Specifications 10 ........................................................................\ .................................. MX2000 Compot~ent Placement 11 MX2000 Schematic ........................................................................\ .................................................... 12 ........................................................................\ ....................... MX2000 Pri~i~ary Wiring Information 13 ........................................................................\ .... MX 1500 AMPLIFIER CIRCUIT DESCRIPTION 14 ........................................................................\ ....... MX'I 500 & MX2000 CIRCUIT DESCRIPTION 14 ........................................................................\ .............................................. Power Supply 14 ........................................................................\ ............... Complementary Output Tralsistors 15 ................. . Complemerttary Driver Transistors, Crossover Bias, and HighILors~ iver circuit 15 ............ ................................... Balanced Illput Circuit. Gain Col~trol, and Frequency Limits .. 16 ....... Amplifier Feedback Network, Gain Stage, Distortion LED, atld S11o: ':lircuit Protection 17 ...................................................................... Output Protection and Signal Readout Circuits 18 ........................................................................\ ............................ Input/O~ltput Coni~ections 1 9 .......................................................... TROUBLESHOOT1 NG THE MX 1 500/MX2000 A MPLIFTER 20 ........................................................................\ .............................. Excessive Current Draw -20 ........................................................................\ .................... Signal Amplification Problems 20 ........................................................................\ ............................. Poor Freqi~ei~cy Response 21 ........................................................................\ .................................................. Gain Wrong 22 ........................................................................\ ......... Incorrect Short Circrrit Current Litnits 22 ........................................................................\ ................ D.C. Fault Without Current Draw 22 ........................................................................\ ............... Protection Circuit Troubleshooting 22 ........................................................................\ ................................. Relay Won't Come On 23 ........................................................................\ ......... ....................... No Red "Protect" LED ., 23 ........................................................................\ ............................................ No M~lting Delay 23 ........................................................................\ ...................................... Excess Muting Delay 23 ........................................................................\ ....................................... No Tliennal Sliutoff 23 ........................................................................\ ............................................... No DC Protect 23 ......................... ...................................... Relay Fa~~lts With Nor~nally Operating Amplifier ... 24

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MX15QQ Specifications OUTPUT POWER (per channel): Continuous Average Output Power both channels driven. 8 ohms, 20 - 2OkHz 0.1% THD 330 8 ohms, I kHz 1% THD360 4 ohms, 20 - 20khz 0.1% THD 500 4 ohms, I kHz 1% THD570 2 ohms, I kHz 1% THD 750+/-IdB BRIDGED MONO OPERATION: 16ohms,20-2OkHz 0.1% THD660 16 ohms, I kHz 1% THD720 8 ohms, 20 - 2OkHz 0.1% THD 1000 8 ohms, I kHz 1% THD1100 4 ohms, I kHz 1% THD 1500+/-IdB DISTORTION (8 ohms): THD, 20-20kHz, from 250milliwatts to rated power, less that 0.1%, 0.015% typical. SMPTE-IMD, less than 0.02%, 250 milliwatts to rated power. FREQUENCY RESPONSE: 20-ZOkHz, +/-0.1 dB. 8-300kHz, +0/-3 dB. DAMPING FACTOR: Greater than 200. SLEW RATE: 20V per microsecond. DYNAMIC HEADROOM: 3dB or 1000 watts instantaneous power @ 4 ohms. NOISE: -1 OOdB, 20-20kHZ. SENSITIVITY: 1V RMS for rated power (8 ohms). INPUT IMPEDANCE: 10k unbalanced , 20k balanced. DIMENSIONS: 3 5" tall (2 ra~k spaces), 19" wide, 17 9" deep WEIGHT: 471bs net, 52 Ibs shipping