McIntosh MC-252 manual

MC252 Owner ’ s Manual McIntosh Laboratory , Inc. 2 Chambers Street Binghamton, New Y ork 13903-2699 Phone: 607-723-3512 F AX: 607-724-0549 Power Amplifier[...]

2 IMPOR T ANT SAFETY INSTRUCTIONS! PLEASE READ THEM BEFORE OPERA TING THIS EQUIPMENT . W ARNING - T O REDUCE RISK OF FIRE OR ELECTRICAL SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. The lightning flash with arrowhead, within an equilateral triangle, is intended to alert the user to the presence of uninsulated “dangerous voltage” with[...]

3 Customer Service T echnical Assist ance Please T ake A Moment Thank Y ou Copyright 2003  by McIntosh Laboratory , Inc. The serial number , purchase date and McIntosh Dealer name are important to you for possible insurance claim or future service. The spaces below have been provided for you to record that information: Y our decision to own this[...]

4 Performance Features Introduction • Power Output The MC252 consists of two separate power amplifier chan- nels, each capable of 250 watts into 2, 4 or 8 ohm speakers with less than 0.005% distortion. The two channels can be combined into a single channel with 500 watts into 1, 2, 4, 8 or 16 ohm speakers with less than 0.005% distortion. • •[...]

5 Connector Information, Introduction, Performance Features and Dimensions The following dimensions can assist in determining the best location for your MC252. There is additional informa- tion on the next page pertaining to installing the MC252 into cabinets. 17- 1/2 " 44.45cm 8- 13/16 " 22.38cm Front V iew of the MC252 Rear V iew of the[...]

6 Inst allation Caution: The MC252 Amplifier weight is 94.5 pounds (42.87 kilograms). It requires two or more persons to safely handle when moving the amplifier . The MC252 can be placed upright on a table or shelf, standing on its four feet. The four feet may be removed from the bottom of the MC252 when it is custom installed as outlined below . T[...]

7 T op Panel Connections and Switch Connect the MC252 power cord to a live AC outlet. Refer to information on the back panel to deter- mine the correct voltage BALANCED INPUTS for an audio cable from a preamplifier or control center audio outputs RIGHT Channel OUTPUT s connections for 2 ohm, 4 ohm and 8 ohm Loudspeakers Main Fuse holder, refer to i[...]

8 Caution: The supplied AC Power Cord should not be connected to the Rear Panel of the MC252 Amplifier until after the Loudspeaker Connections have been made and the supplied protective T erminal Connection Covers have been inst alled. Failure to observe this could result in Electric Shock. 1. For Remote Power Control, connect a power control cable[...]

9 How to Connect in Stereo T o AC Outlet 4 ohm Loudspeaker McIntosh C45 Audio Control Center MC252 T op Rear V iew 4 ohm Loudspeaker[...]

10 Caution: The supplied AC Power Cord should not be connected to the Rear Panel of the MC252 Amplifier until after the Loudspeaker Connections have been made and the supplied protective T erminal Connection Covers have been inst alled. Failure to observe this could result in Electric Shock. There are two different ways of operating the MC252 mon- [...]

11 How to Connect in Mono Bridged Mode T o AC Outlet 4 ohm Loudspeaker McIntosh C45 Audio Control Center MC252 T op Rear V iew M ono B r idge H ookup C onne cti ons Louds pe ak e r I mpe danc e Loudspe aker N egat iv e ( -) Connec t ion Loudspe ak e r P os it iv e (+ ) Conne ct ion 4 S (O h m ) Le f t O ut p ut 2 S Po sitive (+ ) Co nne ct ion Ri g[...]

12 Caution: The supplied AC Power Cord should not be connected to the Rear Panel of the MC252 Amplifier until after the Loudspeaker Connections have been made and the supplied protective T erminal Connection Covers have been installed. Failure to observe this could result in Electric Shock. There are two different ways of operating the MC252 mon- a[...]

13 How to Connect in Mono Bi-Amp (Parallel) Mode M ono B i - A m p (P ar al le l ) H o okup C onne ct ion s Loudspe ak e r I mpe danc e Loudspe ak e r Negat i v e (- ) Connect ion Loudspe ak e r P os it iv e (+ ) C onnect ion 1 S (O h m ) Lef t and R ig ht O ut p ut 2 S N eg at iv e (- ) Co nn ect io n Lef t and R ig ht O ut p ut 2 S Po siti v e (+[...]

14 Front Panel Displays and Controls METER indicates the Power Output of the Left Channel Amplifier METER Switch selects the display modes of the Power Output Meter POWER GUARD LED lights when the amplifier Right Channel POWER GUARD circuit activates POWER Switch T urns AC power On/Off, or On/Remote Remote On Indicator lights when the amplifier is [...]

15 How to Operate How to Operate Power On T o have the MC252 automatically turn On or Off when a control center turns on or off , rotate the power switch to the remote position. For manual op- eration, rotate the power switch to the On or Off position as de- sired. Refer to figure 10. Note: Ther e must be a power control connection between the MC25[...]

16 T echnical Description McIntosh Laboratory , the company who introduced the world’ s first amplifier that could be called “High Fidelity”, has done it again. The McIntosh engineering staff has cre- ated a power amplifier without compromise, using the most advanced McIntosh circuit design concepts. A continuous average power output rating o[...]

17 T echnical Description rent gain over the entire current range they must cover . Output transistors in particular , have matched uniform cur- rent gain, high current-bandwidth product and large active region safe operating area. An automatic tracking bias sys- tem completely eliminates any trace of crossover distor- tion. Precision metal film re[...]

18 Figure 19 W ith Power Guard Figure 18 W ithout Power Guard Figure 17 Input T est Signal Figure 16 lower than optimum, causes more output current to flow , which results in extra heat being generated in the power output stage. This increase in temperature will result in a reduced life expectancy for the amplifier . The Autoformer creates an ideal[...]

19 T echnical Description, con’t tronic attenuator at the amplifier input reduces the input volume just enough to prevent any further increase in dis- tortion. The Power Guard circuit acts so fast that there are absolutely no audible side effects and the sonic purity of the music reproduction is perfectly preserved. The MC252 Power Amplifier with[...]

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21 Notes[...]

22 Specifications Specifications Power Output S tereo Minimum sine wave continuous average power output per channel, all channels operating is: 250 watts into 2 ohm load 250 watts into 4 ohm load 250 watts into 8 ohm load Power Output Mono Bridged Minimum sine wave continuous average power output is: 500 watts into 4 ohm load 500 watts into 8 ohm l[...]

23 Packing Instructions Packing Instructions Quantity Part Number Description 1 034256 Shipping carton only 2 034250 Foam end cap 1 034198 Inner carton top 1 034199 Inner carton bottom 1 034188 Foam pad 1 034037 Inner carton pad 1 033699 Shipping skid 7 017218 Plastic foot 4 100159 #10-32 x 3/4” Machine screw 2 104083 #10 x 7/16” Flat washer 3 [...]

McIntosh Part No. 040815 McIntosh Laboratory , Inc. 2 Chambers Street Binghamton, NY 13903 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.[...]