User manual MCINTOSH C26

[. . . ] THE MclNTOSH C 26 SOLID STATE STEREO PREAMPLIFIER READING TIME: 32 Minutes Price $1. 25 Your C 26 stereo preamplifier will give you many years of pleasant and satisfactory performance. If you have any questions concerning this instrument, please contact: CUSTOMER SERVICE Mclntosh Laboratory Inc. 2 Chambers Street Binghamton, New York 13903 Phone: 607-723-3512 CONTENTS Service Contract . . . 11 WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE. [. . . ] This can be heard as a howl or squeal in the background when the recordings are played back. This noise is caused by insufficient filtering of the bias oscillator circuits in the tape recorders. A test run should be made for the particular recorders intended for this use. 8 SPEAKER SWITCHES To switch the main and remote stereo speakers using the pushbuttons on the front panel, the power amplifier output leads must be connected to the amplifier output terminals on the rear of the C 26. The main speakers must be connected to the main speaker terminals and the remote speakers to the remote speaker terminals. If either main or remote speaker button is pushed to OFF, load resistors are automatically connected to the power amplifier to compensate for the speaker. The headphone output is always connected through level matching resistors to the amplifier terminals regardless of the position of the main or remote switches. Using the Front Panel Controls In the upper right of the front panel is the VOLUME-ON/OFF control. The VOLUME control has been precision tracked throughout the listening range (0 to -65 dB) for accurate stereo balance. MODE SELECTOR: Connects the program to the loudspeaker in the following seven ways: L to L & R: Connects the "left" input to both loudspeakers. R to L & R: Connects the "right" input to both loudspeakers. STEREO REV: Connects the "left" input to the "right" loudspeaker and the "right" input to the "left" loudspeaker. STEREO: Connects the "left" input to the "left" loudspeaker and the "right" input to the "right" loudspeaker. MONO (L + R): adds the "left" input and the "right" input and then connects the L + R program to both amplifiers and loudspeakers. L + R to L: Connects the "left plus right" program to the "left" loudspeaker only. L + R to R: Connects the "left plus right" program to the "right" loudspeaker only. INPUT SELECTOR: Aux: Connects the output from any high level program source requiring flat amplification to the high level input stage. Such a source could be a tele- vision set or other source that has output of 0. 25 volts or more. In the AUX position the gain is 20 dB to the MAIN outputs, 0 dB to the TAPE outputs. TAPE 1: Connects the output from a complete tape recorder to the high level input stage of the C 26. TAPE 2: Connects the output from a complete tape recorder to the high level input stage of the C 26. TUNER: Connects the output from any AM, FM or FM STEREO tuner to the high level input stage of the C 26. PHONO 1: Connects the output of any magnetic phono cartridge to the low level input stage of the C 26. The response has been shaped to compensate for the characteristics of the magnetic phono cartridge. [. . . ] Again negative feedback is used to assure low distortion and, in addition, accurately shapes the tone-control response curves and provides a low output impedance for the main outputs. Negative feedback is maintained at all frequencies, even with the tone controls turned to full boost. CENTER CHANNEL AMPLIFIER (L + R) The center channel amplifier is a single transistor connected as a voltage amplifier. The main left and right outputs are fed through mixing resistors to the input of the voltage amplifier. [. . . ]