McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: 607-723-3512 www.mcintoshlabs.
Important Safety Information is supplied in a separate document “Important Additional Operation Information Guide” Thank You from all of us at McIntosh Table of Contents You have invested in a precision instrument that will provide you with many years of enjoyment. Please take a few moments to familiarize yourself with the features and instructions to get the maximum performance from your equipment.
Connector Information Power Control Connector The MI1250 Power Control Input receives an On/Off signal from +5 to +12 volts. The Power Control Output will in turn provide a +12 volt Output Signal with a total current up to 50mA. An additional connection is for controlling the illumination of the MI1250 Meter Power Power Output Indicators. The Control Meter 3.5mm stereo mini phone Illumination plug connects to a McIntosh Control Ground Preamplifier or A/V Control Center Power Control Output.
16-7/8" Installation The MI1250 needs to be placed upright on its four feet. It also can be custom installed. Remove the four feet when it is custom installed and retain them with the fastening screws for possible future use. The required panel cutout, ventilation cutout and unit dimensions are shown in the drawing on the right side of this page. It is necessary to provide adequate ventilation for cool operation, ensuring long life for the unit. Do not install the MI1250 above heat generating components.
Dimensions Front View of the MI1250 17-1/2" The Following Dimensions Can Assist In Determining The Best Location For Your MI1250. 44.5cm 3-15/32" 4- 5/16" 8.8cm 11.0cm Side View of the MI1250 17-1/2" Front View of the MI1250 with Side Mount Brackets 19" 17-1/16" 48.3cm 44.5cm 47.0cm 3/16" .5cm 3-1/4" 8.2cm .25" 13-1/4" .64cm 33.7cm 2.0" 5.0cm 13-19/32" 34.7cm 1- 5/16" 3.
Audio Input Selection for each Power Amplifier Channel Each Channel of the MI1250 allows selection of different Audio Signal Inputs to be Amplified after selected via the two switches. The first switch LOCAL/BUS selects between the specific Channel Unbalanced Input Jack or BUS which allows selection of the BUS Switch (1, 2, D1 or D2). The BUS Switch allows selection of the following: BUS 1 - Unbalanced Input Jack (L or R) dependent by its Channel Type.
IN OUT L + – R L + – + – R L + – + – R L + – + – R L + – + – STEREO MONO R L + – + – STEREO CHANNEL 1 MONO CHANNEL 3 STEREO MI 1250 1 2 D1 D2 LOCAL BUS CHANNEL 2 MONO VOL 1 2 D1 D2 LOCAL BUS CHANNEL 4 STEREO CHANNEL 5 MONO VOL 1 2 D1 D2 LOCAL BUS CHANNEL 6 STEREO CHANNEL 7 MONO VOL 1 2 D1 D2 LOCAL BUS CHANNEL 8 STEREO CHANNEL 9 MONO VOL 1 2 D1 D2 LOCAL BUS R 12 CHANNEL POWER AMPLIFIER McINTOSH LABORA TORY, INC.
Screws Output Plug Connection When connecting the Loudspeaker Hookup Cables to the MI1250 using the supplied Loudspeaker Connection Plugs. 1. To minimize power losses in the hookup cables, use cables with the largest wire thickness that will physically fit in your application: American Wire Gauge (AWG) specifies cable wire thickness. A smaller AWG number represents a larger wire thickness. Reference the following table as a guideline.
Loudspeaker Socket. Then connect the opposite end of the Loudspeaker Hookup Cable to the Loudspeaker Connection Terminals. Make sure to match up the MI1250 Negative and Positive Output Connection on the Plug Connector, with the Loudspeaker Negative and Positive Input Connections. WARNING: Loudspeaker terminals are hazardous live and present a risk of electric shock. For additional instruction on making Loudspeaker Connections contact your McIntosh Dealer or McIntosh Technical Support. 9.
POWER switch controls AC On or Off Front and Rear Panel Displays Front Panel Display LED indicates Channels 1 - 12 Circuitry Functions BUS 1 and 2 left and right input and outputs Volume controls for each channel Channel input switches to select from connected analog and digital sources LED Standby Power On Indicator Mono / Stereo select switch for each channel pairing Main fuse - please refer to rear panel markings for proper fuse size and rating Rear Panel Display AC power input Digital Optical
Specifications Power Output Minimum sine wave continuous average power output per channel, all channels operating is: 50 watts into a 8 ohm load 90 watts into a 4 ohm ohm load Output Load Impedance 8 and 4 ohms Rated Power Band 20Hz to 20,000Hz Total Harmonic Distortion 0.05% maximum harmonic distortion at any power level from 250 milliwatts to rated power, 20Hz to 20,000Hz Dynamic Headroom 2.1dB, 8 ohm load 3.3dB, 4 ohm load Frequency Response +0, -0.
McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, NY 13903 www.mcintoshlabs.com The continuous improvement of its products is the policy of McIntosh Laboratory Incorporated who reserve the right to improve design without notice. Printed in the U.S.A. McIntosh Part No.