CONTENTS Amplifier 11-14 Performance Specifications 3 Notes 3 Control and Balance Control 14-18 Rear Panel 4 Treble 19 Bass 20 Front Panel and Trim Parts List 4 Section Locations 5-6 Speaker Switch 21 Block Diagram 5-6 AC Power Supply 22 Interconnection Diagram 6-9 DC Power Supply 23 Repacking Instructions 24 Input/Output (Left and Right) 10-12 Mclntosh Laboratory, Inc.
Performance Specifications FREQUENCY RESPONSE + 0, -0.5dB from 20Hz to 20,000Hz INPUT IMPEDANCE Phono: 47K ohms and 65pF Capacitance High Level: 22K ohms RATED OUTPUT 2.5V at MAIN and SWITCHED 1 and 2, and BALANCED OUTPUTS TONE CONTROLS Bass and Treble stepped, 20dB boost to 20dB cut MAXIMUM VOLTAGE OUTPUT More than 8V at all outputs AC POWER OUTLETS 4 switched and 1 unswitched, Total capacity 1400 watts TOTAL HARMONIC DISTORTION 0.002% maximum IHF, 0.
Rear Panel Fig.
Section Locations Block Diagram INTERCONNECTION PARTS LIST Symbol Part CAPACITORS C1.C2 061276 DISC CAP, .0047uF, 400VAC JACKS J2,J3 J4,J5 117563 117437 Phone Jack XLR Connector, Male LIGHTING DEVICES DS1.DS2 058138 DS3.
Interconnection Diagram 7 8 9
Input/Output, Left and Right LEFT INPUTS/OUTPUTS PCB 048481 AND RIGHT INPUTS/OUTPUTS PCB 048476 INPUT/OUTPUT PARTS LIST Symbol RELAYS K1,K7,K9, K11,K12 K2-K6.K8, K10,K13-K16 Part 087056 087050 Description Form 1C, 5VDC, Reed, HE3321C0500 SPST. 5VDC, Reed, HE3321A0400 AMPLIFIER PCB 048474 10 11 12 AMPLIFIER PARTS LIST Symbol Part Description RELAYS K1-K4 087056 Form 1C, 5VDC, Reed, HE3321C0500 DIODES D1.
NOTE: Components and values toned in gray warrant your attention; parenthesized values apply to serial numbers L K 1 0 0 1 - L K 1 9 8 9 . nonparenthasized values apply to serial numbers LK1990 and above.
Control and Balance Control 15 16
Control and Balance Control CONTROL PCB 048479 BALANCE CONTROL PCB 048478 CONTROL PARTS LIST BALANCE CONTROL PARTS LIST Symbol Part Description RESISTORS and POTENTIOMETERS R1 134475 Balance Control Symbol Part DIODES D1-D32 070047 INTEGRATED CIRCUITS IC1 133189 IC2 133108 17 Description SIG, 75V, 150mA, 1N4148 Dual Op-Amp.
Bass Treble TREBLE PARTS LIST TREBLE PORTION OF PCB 048477 19 BASS PARTS LIST Symbol Part SWITCHES S4.S5 146240 Description Bass/Treble Switch Symbol Part SWITCHES S1.
Speaker Switch SPEAKER SWITCH PARTS LIST SPEAKER SWITCH PORTION OF PCB 048477 21 Symbol Part Description DIODES D1-D6 070047 SIG DIODE 1N4148 SWITCHES S3 146241 Speaker Switch
WARNING: Parts located in the below shaded area have critical characteristics. Use ONLY replacement parts recommended by the manufacturer. AC POWER SUPPLY PORTION OF PCB 048471 AC POWER SUPPLY PARTS LIST 22 Symbol Part Description CAPACITOR C9 061276 Disc Cap, .
DC Power Supply WARNING: Parts located in the below shaded area have critical characteristics. Use ONLY replacement parts recommended by the manufacturer. NOTE: Components and values toned in gray warrant your attention; parenthasized values apply to serial numbers LK1001-LK1989, nonparenthasized values apply to serial numbers LK1990 and above. DC POWER SUPPLY PARTS LIST DC POWER SUPPLY PORTION OF PCB 048471 23 Symbol Part DIODES D1.
Repacking Instructions In the event it is necessary to repack the unit for shipment, the unit must be packed exactly as shown below. IMPORTANT - The four plastic feet must be attached to the bottom of the unit so they will locate in the four holes of the bottom pad. Failure to do this will result in shipping damage. If a shipping carton or any of the interior parts is needed, please call or write the Customer Service Department of Mclntosh Laboratory. Order parts from the accompanying list by part number.
