User manual MCINTOSH MC502

[. . . ] THE MclNTOSH MC 502 POWER AMPLIFIER Reading Time: 28 Minutes Price $2. 00 VARIOUS REGULATORY AGENCIES REQUIRE THAT WE BRING THE FOLLOWING INFORMATION TO YOUR ATTENTION. PLEASE READ IT CAREFULLY. WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE. The Mclntosh you have purchased is a Model MC 502. Record that serial number here: Serial Number The model, serial number and purchase date are important to you for any future service. Record the purchase date here: Purchase Date Upon application, Mclntosh Laboratory provides a Three-Year Service Contract. [. . . ] Added resistance causes reduction of damping characteristics, modification of frequency response and reduction in power output. Use lamp cord, bell wire, or wire with similar type of insulation to connect the speakers to the amplifier. In all cases, the leads to and from the speaker should be twin conductor or twisted together. When using 8 ohm speakers and for the normally short distances of under 30 feet between the amplifier and speaker, No. For distances over 30 feet between the amplifier and speaker use larger diameter wire. It is recommended that the DC resistance of the speaker leads be less than 5% of the speaker impedance. Resistance of the leads should be computed for the length of wire both to and from the speaker or speakers. 4 For multiple speaker operation, run separate leads from the amplifier to the speakers. CONNECTING LOUDSPEAKERS FOR STEREO Connect the leads from the left loudspeaker to the Left and Common OUTPUT terminals on the MC 502. Connect the leads from the right main loudspeaker to the Right and Common terminals. CONNECTING ONE LOUDSPEAKER FOR MONO Connect leads from the loudspeaker to the Left and Right OUTPUT terminals on the MC 502. In MONO operation neither output terminal (Left or Right) is at ground potential. Due precaution is required when connecting test instruments since neither terminal can be grounded. AC POWER The amplifier AC power cord is plugged into a 120 volt 50/60 Hz wall outlet. FUSE A 4-amp fuse protects the MC 502 circuits. The fuse does not protect additional equipment connected to the rear panel AC power outlets. Stereophonic Connections PROGRAM SOURCE RIGHT SPEAKER STEREO MONO LEFT SPEAKER MODE PLACE SWITCH IN STEREO POSITION FOR STEREO OPERATION Monophonic Connections PROGRAM SOURCE MODE STEREO MONO SPEAKER PLACE SWITCH IN STEREO POSITION FOR STEREO OPERATION Front Panel Controls and How to Use Them LEFT GAIN Use the left gain control to adjust the volume in the left channel to the desired listening level. RIGHT/MONO GAIN Use the right/mono gain control to adjust the volume in the right channel to the desired listening level. When the MC 502 is connected for monophonic operation and the rear panel Mode Switch in Mono the volume is controlled by the Right/Mono Gain control only. HEADPHONES The output of the front panel HEADPHONE jack has been designed to feed low impedance dynamic stereo headphones. Adjust the front panel LEFT GAIN and RIGHT/MONO GAIN control for comfortable headphone listening. Electrostatic headphones generally require higher power than dynamic headphones. Connect them to the LEFT and RIGHT OUTPUT contacts on the back of the MC 502. SPEAKERS OFF: The loudspeakers are turned off when the SPEAKER switch is in the OFF position. THE SPEAKER SWITCH MUST BE IN THE "ON" P O S I T I O N TO H E A R MUSIC F R O M T H E LOUDSPEAKERS. In the mono mode of operation only the Right (MONO) channel input jack accepts signal and the Left channel input jack is disconnected. INPUT LEVEL The input sensitivity of the MC 502 is 0. 75 volts or 2. 5 V depending on the position of the INPUT LEVEL switch. [. . . ] Clipping is caused when the amplifier is asked to produce more power output than it can deliver with low distortion. The extra energy content of the clipped signal will damage most loudspeakers, particularly delicate high frequency tweeters. A new Mclntosh advancement helps protect your speakers from this kind of damage. The MC 502 has a built-in waveform comparator which compares the wave shape of the output signal to the input signal. [. . . ]