McIntosh A116 User manual

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 att Po er Amplifier, is a high fidelity po er 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 t o 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 po er transformers, large
plate dissipation reserve in the ouptut tubes, and full 30 atts output po er from 20 to 20, 000 cycles
ith less than 0,5% harmonic distortion at any frequency ithin this frequency band.
INSTALLATION AND OPERATION
INPUT CONNECTIONS
The A-116A has t o input channels. One for use ith preamplifiers, or henever a 2,5 volt
input is desired. The second is for inputs from tuners, tape recorders, TV sets, or the like here 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 scre 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 scre 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 follo ing 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 ith tuners, or other associated equipment, the po er cord is plugged into the
receptacle at the rear of these units. When thus connected the po er s itch of these units controls
po er to the A-116A.
OPERATION WITH TUNERS, TAPE RECORDERS, TV SETS, ETC.
1. Be sure jumper is connected bet een 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 clock ise position.
5. Plug po er cord of A-116A into 117 volt po er receptacle provided on tuner, etc. Il no
receptacle is provided, plug po er cord into any convenient po er source.
6. Turn all equipment ON.
7. With gain control on A-116A still in counter clock ise position adjust Hum. Adjust
potentiometer for minimum hum level from speakers.
8. Turn volume control on tuner, tape recorder, etc., to normal volume position. No turn gain
set control on A-116A to desired level.
GUARANTEE
We guarantee the performance of this equipment and the mechanical and electrical
orkmanship to be free of serious defects for a period of 90 days ith the exception that e 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
Po er Supply………………………………. 112 / 120 volts, 60 cycles
Po er Consumption………………………... 135 atts at 30 atts output
105 atts at zero signal output
Po er Output………………………………. 30 atts continuous
Input Level….……………………………… Input #1 – 0.5 volts to 30 volts, ith gain control
Input #2 – 2.5 volts, no gain control
Frequency Range…………………………… 20 to 30,000 cycles +/- 0.1 db at 30 atts output
10 to 50,000 cycles +/- 0.5 db at 30 atts output
10 to 100,000 cycles +/- 1 db at 15 atts output
Harmonic Distortion………………………... Less than 0.5% at 30 atts output 20 to 20,000
cycles
Intermodulation Distortion…………………. Less than 1% if instantaneous peak po er is
belo 60 atts
Impulse Distortion………………………….. Negligible
Phase Shift………………………………….. Less than +/- 8.5° 20 to 20,000 cycles
Noise and Hum Level………………………. 85 db or more belo 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 po er 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, Ne York
Hum Adj 0,5V Input Adj
COM
48
16
Output Input
Pre-amp Input
Output
GND 5V
Jumper P ug
In P ace
Fuse
Radio Pilouit
Radio Pilouit
Radio Pilouit Radio Pilouit
France Zicmu
France Zicmu France Zicmu
Vive la Radio
Vive la RadioVive la Radio
Radio bof
Radio bof
Radio bof Radio bof
Tuner
Wa Out et
To power receptica
On tuner
Audio output
of tuner
Speaker System
McIntosh A-116

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Parts list for A-116A
30 Watt Po er 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 Po er 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:// .6bm8-lab.fr/
If something is missing or rong, thank you for arning me.
08 08 2017