User manual MCINTOSH MC2300

[. . . ] THE MclNTOSH MC 2300 SOLID STATE STEREO POWER AMPLIFIER Price $1. 25 The Mclntosh MC 2300 is a high quality, extremely high power, solid state stereo amplifier. Because of the high power available it is necessary to emphasize some prudent and safe operating conditions. Never connect or disconnect inputs or outputs while the amplifier is turned on. Loudspeakers can be damaged or destroyed by the high power available from the instrument. [. . . ] 0: In this position of the meter range switch, the amplifier will deliver 300 watts when the meter indicates + 3 dB, with meter indication of "0, " the amplifier delivers 150 watts, with a meter indication of --3 dB, the amplifier delivers 75 watts. --10: In this position of the meter range switch, the amplifier will deliver 15 watts output when the meter indicates "0. " --20: In this position of the meter range switch, the amplifier will deliver 1. 5 watt when the meter indicates "0. " Two meters monitor and indicate the output power in each channel. To assure more accurate indications of peak power, Mclntosh's peak locking circuits stretch the peak reading of rapid changing information long enough to give adequate visual perception. Ordinary meters lack the capability of indicating the short interval of power in a sound wave. The mass of the meter movement is too great to respond to the nearly instantaneous changes in music program material. Mclntosh has developed circuits that permit the meters of the MC 2300 to respond to the short interval power in a sound wave to an accuracy of 98%. 8 Monitoring of the output power is done at the primary or input of the autoformer resulting in true power readings regardless of output impedance selected. The graph represents the relationship between the meter reading and power output for all three meter ranges: POWER The power switch turns the MC 2300 on or off. If you wish to control the on/off operation of the amplifier remotely, use a control relay in series with the power line and leave the power switch in the ON position. Do not plug the MC 2300 into any of the auxiliary AC power outlets of the preamplifier or other associated equipment unless that equipment has power capacity for handling 1400 watts (14 amperes). Performance Limits PERFORMANCE GUARANTEE Performance Limits are the maximum deviation from perfection permitted for a Mclntosh instrument. We promise you that the MC 2300 you buy must be capable of performance at or exceeding these limits or you qet your money back. Mclntosh is the only POWER OUTPUT STEREO: 300 watts continuous, both channels operating; which is: 12. 2 volts RMS across 0. 5 ohm 17. 3 volts RMS across 1 ohm 24. 5 volts RMS across 2 ohms 34. 6 volts RMS across 4 ohms 49. 0 volts RMS across 8 ohms 69. 3 volts RMS across 16 ohms MONO: 600 watts continuous; which is: 12. 2 volts RMS across 0. 25 ohm 17. 3 volts RMS across 0. 5 ohm 24. 5 volts RMS across 1 ohm 36. 6 volts RMS across 2 ohms 49. 0 volts RMS across 4 ohms 69. 3 volts RMS across 8 ohms HARMONIC DISTORTION Stereo: Less than 0. 25% at 300 watts output from 20 Hz to 20, 000 Hz both channels operating. INTERMODULATION DISTORTION Stereo: Less than 0. 25% if instantaneous peak power is 600 watts or less per channel with both channels operating for any combination of frequencies 20 Hz to 20, 000 Hz. Mono: Less than 0. 25% if instantaneous peak power is 1200 watts or less for any combination of frequencies 20 Hz to 20, 000 Hz. FREQUENCY RANGE Stereo: 20 Hz to 20, 000 Hz, +0 - 0. 5 dB at rated power; 1, 4, 8 or 16 ohms 20 Hz to 20, 000 Hz, + 0 - 1 . 0 dB at rated power; 0. 5 and 2 ohms 12 Hz to 35, 000 Hz, +0 - 1. 5 dB at one-half rated power Mono: 20 Hz to 20, 000 Hz, +0 - 0. 5 dB at rated power; 0. 5, 2, 4 or 8 ohms 20 Hz to 20, 000 Hz, + 0 - 1 . 0 dB at rated power; 0. 25, and 1. 0 ohms 9 12 Hz to 35, 000 Hz, +0 - 1. 5 dB at one-half rated power NOISE AND HUM 90 dB below rated output OUTPUT POWER MONITOR METER Meter is calibrated to read +3 db when amplifier produces 300 RMS watts or 600 peak watts. Meter range switch is provided to increase meter sensitivity by 10 dB or 20 dB. Meter features special circuit to respond to peak values of complex input signal. Calibration accuracy at 0 dB is ±2% at all frequencies; meter range accuracy is ±5%. OUTPUT IMPEDANCE Stereo: 0. 5, 1, 2, 4, 8, and 16 ohms Mono: 0. 25, 0. 5, 1, 2, 4, and 8 ohms OUTPUT VOLTAGES 25 volts, stereo and mono; 70 volts, stereo and mono DAMPING FACTOR 27 at 0. 5 ohm output, 50 at 1 ohm output, 29 at 2 ohm output, 21 at 4 ohm output, 14 at 8 ohm output. INPUT IMPEDANCE 200, 000 ohms INPUT SENSITIVITY 0. 5 volts input required to produce rated output. POWER REQUIREMENTS 120 volts, 50/60 Hz, 160 watts at zero signal output. [. . . ] (Patented) Diode D203 and resistor R217 tied to the negative supply place a bias on the emitter of transitor Q201 to hold the transistor just at the threshold of conduction. Diode D201 passes only the positive portions of the input signal to the base of Q201 charging the capacitor C201. Since the transistor Q201 is on the edge of conduction the slightest positive swing of input signal causes conduction to begin. The largest capacitor C203 in the emitter circuit will appear as a direct short at first to the negative supply thereby accelerating the needle of the meter upscale. [. . . ]