McIntosh MA 5100 Operating and installation instructions

MA 5100
PREAMP- AMPLIFIER
SERVICEINFORMATION
STARTING WITH SERIAL NO. 21HOO
MclNTOSHLABORATORYINC.2 CHAMBERSSTREETBINGHAMTON,NEWYORK
MA5100

MA 5100ELECTRICALSPECIFICATIONS
PowerOutput:
90wattsRMScontinuous,45wattsperchanneloperatingsimultaneouslyinto
4ohmor8 ohmloads.
60wattsRMScontinuous,30wattsperchanneloperatingsimultaneouslyinto
16ohmloads.
HarmonicDistortion:
Lessthan0.25%atratedpoweroutputfrom20Hzto20,000Hzwithbothchan-
nelsoperating.
IntermodulationDistortion:
Lessthan0.25%foranycombinationoffrequenciesfrom2QHzto20,000Hz
ifinstantaneouspeakpoweris90wattsperchannelorlessinto4 or8 ohm
loadsand60wattsperchannelorlessinto16ohmloadswithbothchannels
operating.
FrequencyRange:
Atratedoutputbothchannels:±0.5dB20Hzthrough20,000Hz.
OutputImpedance:
4ohm,8 ohm,16ohm.Noimpedanceswitchingrequired.
InternalImpedance/Damping:
Lessthan.04ohms;dampingfactorgreaterthan100.
InputSensitivityAndImpedance:
Auxiliary,Tape,Tuner,andTapeMonitor:300mV,250Kohms.
Phono1 andPhono2:2mV,47,000ohms.
TapeHead:2mV,1/2megohm.
HumAndNoise:
HighLevelInputs:75dBbelowratedoutput.
LowLevelInputs:70dBbelow10mVinput.
PowerAmplifier:90dBbelowratedoutput.
TapeOutput:
300mVatratedsensitivity,1.4voltswith10mVatphonoinput.
LeftPlusRightOutput:
Adjustable 0 to6 voltsfromgeneratorimpedance of lessthan 5,000 ohms.
BassControls:
+18dBat20Hz.
TrebleControls:
+l8dBat20,000Hz.
HFFilter:
Flat,or5,000Hzcutoff.
LPFilter:
Plat,or50Hzcutoff.
PowerRequirements;
117voltsAC,50-60Hz,70wattsatzerosignaloutput,200wattsatrated
output.

MA
5100
BLOCK
DIAGRAM
MA 5100

MA 5100
PREAMP.SECTIONPRINTEDCIRCUITBOARD
043-989

PREAMP.SECTION
MA5100154-411
HEAVY LINE SHOWS PRIMARY SIGNALPATH

POWEROUTPUT
SECTION
MA5100154-376
HEAVYLINESHOWSPRIMARYSIGNALPATH

MA 5100
OUTPUTMONITORPRINTEDCIRCUITBOARD 043-821
(NOTE1 )
LEFTCHANNELPOWEROUTPUTSECTIONPRINTEDCIRCUITBOARD043-919
RIGHTCHANNELPOWEROUTPUTSECTIONPRINTEDCIRCUITBOARD 043-919

FILTERSECTION
MA5100154-410
FILTERSECTIONPRINTEDCIRCUITBOARD
043-990
MA 5100FILTERSECTIONPRINTEDCIRCUITBOARD043-990

SCHEMATICNOTES
MA 5100
Unlessotherwisespecified:Resistancevaluesareinohms,1/2watt,and10%
tolerance; capacitance values smaller than 1 arein microfarads (mfd); capacitance
valuesgreaterthan1 areinpicofarads(pF); inductorsareinmicrohenries(µH).
Printed circuit board components are outlined onthe schematics by dotted lines.
The circled numbers onthe dotted lines correspond tothe numbers ofthePC board
layouts.
The heavy lines onthe schematicsdenote the primary signal path.
Theterminalnumberingofrotaryswitchesisforreferenceonly.
All voltages indicated onthe schematics are measured under the following condi-
tions:
a.Useofan11 megohm input impedance VTVM,
b.All voltages ±10% with respect to chassis ground.
c.Nosignalatinputterminals,
d.AC input at117 volts AC, 50/60Hz.
e.Frontpanelcontrolsat:
Input Selector
ModeSelector
AUX
STEREO
Volume
Power
MAX
ON
Allothercontrolsinnormalposition.
1.In units with serial numbersbelow 46H01, the output monitor PC board isnot
used.
2.In units with serial numbersbelow44H50: R256 & R25? arenot used; R254&
R255 are120 ohms; transistors Q205 & Q206 (132-021) and potsR221 & R222
(134-120) are used; the emitter of Q2l5 & Q216 is connected as shown bythe
dotted line; C221 & C222 are used.
3.In early units, C5& C6 were 39pF.
4.In units with serial numbersbelow30H15:L201,L202,R241, R242, C215,
C216,C217,andC2l8arenotused;C227,C228,C229,C230,C231,andC232
areused;R229& R230are100ohms;C201& C202are330pF.
5.In early units, C207 & C208 were 200µF, 3V (part number066-086).
6.In units with serial numbersbelow30H30:D201 & D202 were two diodes
(partnumber070-022).
7.In units with serial numbersbelow28H00: C3, C4} C5,C6,R9, R10, and
R314arenotused.
8.In early units, C308 & C309 were 10,000µF, 40V (part number066-090).
9.In units with serial numbersbelow24H05: R237 & R238 are.47 ohms; R233
& R234 are220 ohms; C211,C212,C213, and C2114 are .01µF.
10.In units with serial numbersbelow 23H7S: D211,D212,D213, and D214 are
notused.
11.In units with serial numbersbelow22H00: R227 & R228 were 1K, 10%, 1W,
12.In units with serial No'sbelow54H60: R254 and R255 are18and F201,
F202,F203j and F204 are3A fuses. (Part Ho. 089019)
LOCATIONOFTRANSISTORSNOTONPRINTEDCIRCUITBOARDS

POWER
SUPPLY
SECTION
MA
5100
154-331
MA 5100