INSTRUCTION MANUAL McINTOSH MODEL A116 30 WATT POWER AMPLIFIER

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McINTOSH MODEL A-116A INSTRUCTION MANUAL The McIntosh Model A-116A, 30 watt Power Amplifier, is a high fidelity power amplifier designed to meet the exacting requirements of professional applications and home entertainment systems. Outputs from a preamplifier-equalizer, from a tuner, or other signal source delivering 0,5 volt or more are handled by the unique two channel input system. Output impedances for direct connection to loudspeakers or a 600 ohm line are provided. Several of the outstanding features of the A-116A amplifier are: incorporation of the famous McIntosh high efficiency output circuit, hermetically sealed output and power transformers, large plate dissipation reserve in the ouptut tubes, and full 30 watts output power from 20 to 20, 000 cycles with less than 0,5% harmonic distortion at any frequency within this frequency band.

INSTALLATION AND OPERATION INPUT CONNECTIONS The A-116A has two input channels. One for use with preamplifiers, or whenever a 2,5 volt input is desired. The second is for inputs from tuners, tape recorders, TV sets, or the like where input signals range from 0,5 volts up. A potentiometer is provided on this input channel for gain setting. Connections to the 2,5 volt input are made at the input socket. See schematic diagram. Connections for the 0,5 volt are made either at the input screw terminal strip or the input socket. NOTE – THE INPUT SOCKET MUST BE JUMPED BETWEEN TERMINALS 2 AND 3 TO RENDER THE 0,5 VOLT INPUT OPERATIVE. OUTPUT CONNECTIONS The A-116A has output impedance of 4, 8, and 16 ohm available at either the screw terminal connector or the output socket. In addition, 600 ohm (balanced to ground) is available at the output socket. Because many loudspeakers do not have voice coil impedances exactly matching 4, 8, or 16 ohms, the following table lists suggested connections for best impedance matching. Speaker impedance

3,2 to 6,5 ohms

6,5 to 13 ohms

13 ohms to 32 ohms

Connect to

4 ohms

8 ohms

16 ohms

WARNING: OUPUT PLUGS WIRED FOR McINTOSH 20W-2 and 50W-2 AMPLIFIERS WILL NOT FUNCTION WITH THE A-116A WITHOUT RE-CONNECTION.

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POWER CONNECTIONS When used with tuners, or other associated equipment, the power cord is plugged into the receptacle at the rear of these units. When thus connected the power switch of these units controls power to the A-116A.

OPERATION WITH TUNERS, TAPE RECORDERS, TV SETS, ETC. 1. Be sure jumper is connected between terminals 2 and 3 of A-116A input socket. 2. Connect speaker to A-116A output. 3. Connect output of tuner, tape recorder, TV set, etc., to 0,5 volt input terminals of A-116A. 4. Turn gain control on A-116A to extreme counter clockwise position. 5. Plug power cord of A-116A into 117 volt power receptacle provided on tuner, etc. Il no receptacle is provided, plug power cord into any convenient power source. 6. Turn all equipment ON. 7. With gain control on A-116A still in counter clockwise position adjust Hum. Adjust potentiometer for minimum hum level from speakers. 8. Turn volume control on tuner, tape recorder, etc., to normal volume position. Now turn gain set control on A-116A to desired level.

GUARANTEE We guarantee the performance of this equipment and the mechanical and electrical workmanship to be free of serious defects for a period of 90 days with the exception that we do not guarantee the tubes or filter condensers beyond that of their manufacturers. U.S. Patent No. 2477074 – Other Patents Pending Printed in U.S.A.

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ELECTRICAL AND MECHANICAL SPECIFICATIONS McINTOSH MODEL A-116A POWER AMPLIFIER

Power Supply……………………………….

112 / 120 volts, 60 cycles

Power Consumption………………………...

135 watts at 30 watts output 105 watts at zero signal output

Power Output……………………………….

30 watts continuous

Input Level….………………………………

Input #1 – 0.5 volts to 30 volts, with gain control Input #2 – 2.5 volts, no gain control

Frequency Range……………………………

20 to 30,000 cycles +/- 0.1 db at 30 watts output 10 to 50,000 cycles +/- 0.5 db at 30 watts output 10 to 100,000 cycles +/- 1 db at 15 watts output

Harmonic Distortion………………………...

Less than 0.5% at 30 watts output 20 to 20,000 cycles

Intermodulation Distortion………………….

Less than 1% if instantaneous peak power is below 60 watts

Impulse Distortion…………………………..

Negligible

Phase Shift…………………………………..

Less than +/- 8.5° 20 to 20,000 cycles

Noise and Hum Level……………………….

85 db or more below rated output

Damping Factor……………………………..

12 or better for 4, 8 and 16 ohm outputs, 16 for 600 ohms

Input Impedance…………………………….

0.5 meg from 20 cycles to 40 Kc

Output Impedance…………………………..

4, 8, 16 and 600 ohms (600 ohms is balanced to ground)

Tube Complement…………………………..

Rectifier: 5U4-G Pre-Amp: 12AX7 Phase inverter: 12BH7 Driver: 12BH7 Output: 2 – 6BG6-G

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Auxiliary Equipment Connection…………..

Designed to power preamplifiers

Size………………………………………….

12” x 8” x 8-1/4” high, chassis type construction

Weight………………………………………

33 pounds net

Finish………………………………………..

Gray hammertone

McINTOSH LABORATORY, INC. 320 Water Street Binghamton, New York

McIntosh A-116 Hum Adj

0,5V Input Adj Speaker System

Jumper Plug In Place 16

Fuse

8

4

COM

Output Output

GND

5V

Input

Pre-amp Input

Audio output of tuner To power receptical On tuner

Tuner

Radio Pilouit

France Zicmu

Vive la Radio

France Zicmu

Radio bof

Vive la Radio

Radio Pilouit France Zicmu Radio bof

Wall Outlet

Vive la Radio Radio bof

Radio Pilouit

Radio Pilouit

Radio bof

-5Parts list for A-116A 30 Watt Power Amplifier R1

500K Pot, Level Adj

C1

.033

R2

2.2M

C2

.022

R3

56K, 1W

C3

.1

R4

2.2K

C4

47mmf

R5

18K, 1W

C5

.022

R6

47K

C6

.1

R7

1M

C7

.1

R8

100K

C8

.25, 600V

R9

2.2K

C9

.25, 600V

R10

1M

C10

40/80-20, 500/450V

R11

100K

C11

20, 150V

R12

1K

C12

10, 450V

R13

10K

C13

.0047

R14

22K

C14

.1

R15

1.2M

R16

1M

CR1

Sel. Rect, 4 plate 20 Ma

R17

12K, 2W

R18

12K, 2W

L1

1.5 Micro H. Choke

R19

100K

L2

2.7 Micro H. Choke

R20

1.2K

R21

100K

T1

M-152A Power Trans

R22

12K, 2W

T2

M-150A Output Trans

R23

12K, 2W

R24

680K

V1

12AX7

R25

680K

V2

12BH7

R26

250 Ohm Pot, Hum Adj

V3

12BH7

R27

470 Ohm

V4

6BG6-G

R28

150 Ohm, 10W

V5

6BG6-G

R29

56K

V6

5U4-GA

R30

4.4K, 2W

R31

47K

R32

120K

R33

10K

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Made from original 1953 McIntosh A-116A Instruction Manual. René Conseil - http://www.6bm8-lab.fr/ If something is missing or wrong, thank you for warning me. 08 08 2017