McIntosh MA6500 Service Manual

BLOCK DIAGRAM
7
8
NEGATIVE
CURRENT
LIMITER
POSITIVE
CURRENT
LIMITER
CURRENT
SOURCE
PREDRIVER
POWER
GUARD
DRIVER OUTPUT
DC
BIAS
PREDRIVER DRIVER OUTPUT
ELECTRONIC
ATTENUATOR
LEFT PG
INDICATOR
NEGATIVE
FEEDBACK
VOLTAGE
LOG
AMP
POSITIVE
CURRENT
LIMITER
OUTPUT DRIVER PREDRIVER
DC
BIAS
CURRENT
SOURCE
PREDRIVER DRIVER OUTPUT
PG
INDICATOR
DRIVER
POWER AMP
INPUT
SWITCH
NEGATIVE
CURRENT
LIMITER
VOLTAGE
LOG
AMP
NEGATIVE
FEEDBACK
DIFF
AMP
CASCODE
VOLTAGE
AMP
CASCODE
VOLTAGE
AMP
CASCODE
VOLTAGE
AMP
DIFF
AMP
DIFF
AMP
DIFF
AMP
POWER
GUARD
PG
DRIVER
RIGHT PG
INDICATOR
ELECTRONIC
ATTENUATOR
POWER AMP
INPUT
SWITCH
TO PRE AMP
OUT (INT)
PRE AMP IN
(EXT)
TO PRE AMP
OUT (INT)
CASCODE
VOLTAGE
AMP
RECTIFIER
RECTIFIER
DC
AMP
DC
AMP
+++
---
---
+++
LEFT
METER
RIGHT
METER
SPEAKER
SWITCHING
TURN ON
DELAY
THERMAL
PROTECTION
SPEAKER
SWITCHING
SPEAKER 2
SPEAKER 1
LEFT
OUTPUT
SPEAKER 2
SPEAKER 1
RIGHT
OUTPUT
PRE AMP IN
(EXT)
TO MICRO CONTROLLOR
PRE AMP LEFT
(INT)
PRE AMP RIGHT
(INT)

McIntosh MA6500 Specifications

Power Output

RMS Power Output at 8 ohms	120 W
RMS Power Output at 4 ohms	200 W
RMS Power Output at 2 ohms	250 W

Distortion and Noise

Total Harmonic Distortion	0.005%
Intermodulation Distortion	0.005%
S/N Ratio (A-Weighted) Power amp	110 dB below rated output

Input and Output

Maximum Voltage Output	8 V from 20Hz to 20kHz
Input Sensitivity High level	250 mV for 2.5 V rated output
Maximum Input Signal High level	10 V

Impedance and Gain

Output Load Impedance	2, 4, or 8 ohms
Input Impedance High level	22k ohms
Voltage Gain High level to tape	0 dB

Weight and Dimensions

Dimensions (h x w x d)	13.7 x 44.5 x 46 cm
Weight net	18.6 kg
Weight shipping	27.3 kg