McIntosh MA 2275 Service Manual
This is the 28 pages manual for McIntosh MA 2275 Service Manual.
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Extracted text from McIntosh MA 2275 Service Manual (Ocr-read)
Page 1
PERFORMANCE SPECIFICATIONS 2 1. The heavy lines on the schematic denote the primary signal path. 2. Unless otherwise noted, all voltages indicated on the schematics are measured under the following conditions: a. AC input at 120 volts, 50/60Hz. b. All voltages are +/-10% with respect to ground. A high impedance (10 megaohm) voltmeter must be used. 3. Unless otherwise specified: a. Resistor values are in ohms. b. Capacitor values are microfarads (uF). c. Inductor values are in microhenries (uH).4. On PC board drawings, Square pad indicates: a. Polarized Capacitors - Positive b. Diodes - Cathode c. Others - Pin 1 5.WARNING Parts marked with the symbol have critical characteristics. Use only replacement parts recom- mended by the manufacturer. NOTES Power Output Minimum sine wave continuous average power output per channel, both channels operating is: 75 watts into a 2 ohm load 75 watts into a 4 ohm load 75 watts into an 8 ohm load Rated Power Band 20Hz to 20,000Hz Total Harmonic Distortion Maximum Total Harmonic Distortion at any power level from 250 milliwatts to rated power output is: 0.5% for a 2, 4 or 8 ohm load Frequency Response +0, -0.5dB from 20Hz to 20,000Hz +0, -3dB from 10Hz to 50,000Hz Sensitivity Phono: 4.4mV for 2.5V preamp output High Level: 450mV for 2.5V preamp output Power Amplifier Input: 2.5V for rated output A-Weighted Signal To Noise Ratio Phono Input: 80dB below 10mV input High Level: 97dB below rated output Power Amplifier: 110dB below rated output Intermodulation Distortion Maximum Intermodulation Distortion if instantaneous peak output does not exceed twice the rated output, for any combination of frequencies from 20Hz to 20,000Hz is: 0.5% for a 2, 4 or 8 ohm load Input Impedance Phono: 47k ohms, 65pF High Level: 22k ohms Maximum Input Signal Phono: 90mV High Level: 8V Preamplifier Maximum Voltage Output Phono: 8V High Level: 8V Main Out: 8V at preamp output Voltage Gain High Level to Tape output: 0dB High Level to Preamp output: 15dB Wide Band Damping Factor Greater than 18 Power Requirements 100 Volts, 50/60Hz at 3.6 amps 110 Volts, 50/60Hz at 3.6 amps 120 Volts, 50/60Hz at 3.6 amps 220 Volts, 50/60Hz at 1.8 amps 230 Volts, 50/60Hz at 1.8 amps 240 Volts, 50/60Hz at 1.8 amps Note: Refer to the rear panel of the MA2275 for the correct voltage. Preamplifier Tube Compliment 2 - 12AX7A Phono Circuitry 2 - 12AX7A High Level Circuitry Power Amplifier Tube Compliment 2 - 12AT7 4 - KT88/6550 Overall Dimensions Width is 17-3/4 inches (45.09cm), Height is 10-1/8 inches (25.72cm) including feet, Depth is 18-3/4 inches (47.63cm) including the Front Panel and Knobs Weight 77 pounds (35 kg) net, 110 pounds (50 kg) in shipping carton
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3 MA2275 TOP AND REAR VIEWS PHONOGND EXT SENSOR POWER AMP IN T 4AL 250V SLO BLO 120V 50/60Hz 3 6A PREAMP TAPEOUTPUTS POWER CONTROL SUM DATA PORTS MAINACC SER AL NUMBER MA2275 Mc NTOSH LABORATORY NC BINGHAMTON NY MADE IN USA CAUTIONRISK OF ELECTR C SHOCK DO NOT OPEN CAUTION FOR CONT NUED PROTECT ON AGA NST FIRE HAZARD REPLACE ONLY WITH SAME TYPE AND RATING FUSE CD INPUT INTEGRATED AMPLIFIER L R L R DVD TUNER CD 2 CD INPUTS TAPE 12 AVISRISQUE DE CHOC ELECTR QUE - NE PAS OUVRIR REMPLACER PAR UN FUS BLE DE MEME TYPE AMPERAGE ET VOLTAGE