Two totally identical power amplifier units driven in

● Two totally identical power amplifier units driven in parallel ● Output stage
features novel high-power transistor devices in a dual 8-parallel push-pull
arrangement ● Latest low-noise instrumentation amplifier technology ● MCS+
circuit and current feedback topology in amplification stage ● Support for bridged
use of two M-6200 units with even higher output power ● Strong power supply
with massive high-efficiency toroidal transformer and large filtering capacitors
Supreme monophonic power amplifier takes the product concept to its ultimate conclusion –
Discrete low-noise instrumentation amplifier construction allows fully balanced signal
transmission, augmented by MCS+ circuit and current feedback topology for outstanding
sound and drastically improved S/N ratio. Hefty power supply and two parallel amplification
units, each featuring an 8-parallel push-pull configuration of new high-power transistors
designed specifically for audio applications, sustain 1200 watts (music signals) into an ultra-low
1-ohm load. Output stage with further lowered impedance realizes a damping factor of 1,000.
Monophonic power amplifiers from Accuphase have
always been at the very forefront of the global high-end
audio scene, as demonstrated by many models that have
made history. While positioned as a successor to the
M-6000, the M-6200 approaches the concept of the power
amplifier from a new vantage point. It achieves an
unprecedented level of performance that again redefines
what a monophonic power amplifier can be.
Retaining the parallel arrangement of two completely identical
amplification circuits, the M-6200 drastically lowers the noise
floor and improves the damping factor. Parallel operation has
the advantage of significantly bolstering output current
capability, as well as enabling extremely low output
impedance. Furthermore, improvements to the NFB circuit
using remote sensing and other technological refinements
result in a damping factor in excess of 1,000 and make the
amplifier capable of delivering constant current down to
extremely low impedance loads. In the input stage, parallel
operation along with optimized gain allocation keeps noise
levels to an absolute minimum, as illustrated by the astonishing S/N ratio of 127 dB at maximum gain and 133 dB at the
-12 dB gain setting. Internally, every aspect of the amplifier
has been reworked, and only the very finest parts and
materials are used. Two identical amplification units are driven
in parallel, each featuring an arrangement of newly developed
audio-grade high-power transistors with excellent performance
characteristics. This ensures low impedance of the output and
realizes constant-voltage speaker drive. It is also possible to
use two M-6200 amplifiers in bridged mode for each channel,
thereby creating a system with even more impressive power
output capability, able to deliver 2,400 watts into a 2-ohm load.
Its bold and massive appearance notwithstanding, the M-6200
is a monophonic amplifier that not only impresses through
abundant power and effortlessly dynamic performance but that
reaches to the very heart of the music, expressing even the
most delicate and minute details with stunning realism.
Features and Functions
■ Two units driven in parallel, each with an 8-parallel push-pull arrangement
of high-power transistors deliver linear power progression: 1,200 watts
(music signals) into 1 ohm, 600 watts into 2 ohms, 300 watts into 4 ohms, or
150 watts into 8 ohms.
■ Strong power supply with massive high-efficiency toroidal transformer in
diecast aluminum enclosure and two large 48,000 µF filtering capacitors.
■ Balanced inputs shut out external noise interference.
■ Low-noise instrumentation amplifier topology in discrete configuration
allows balanced signal paths.
■ Printed circuit boards made from glass cloth fluorocarbon resin with low
dielectric constant and minimum loss.
■ MCS+ (Multiple Circuit Summing) and current feedback principle work
together for drastically enhanced S/N ratio.
■ 4-stage gain selector (MAX, -3 dB, -6 dB, -12 dB) also minimizes residual
noise.
■ Phase selector accommodates both pin 2 ⊕ and pin 3 ⊕ type balanced input
sources.
Large high-efficiency
toroidal transformer
Filtering capacitors with
high capacitance
Input amplifier/protection circuit assembly
Line/balanced input connectors
Pre-stage/drive stage power supply assembly
■ Bridged operation of two M-6200 units allows upgrade to monophonic
amplifier capable of delivering 2,400 watts into 2 ohms (music signals).
■ Large analog peak-reading meter:
●
●
Meter operation and illumination on/off switch
Switchable peak hold time: 3 seconds or infinite
■ Protection circuitry uses non-contact semiconductor (MOS-FET) switches
with high voltage rating.
■ Oversize speaker
terminals also accept Y
lugs.
■ Remote sensing
technology using
balanced feedback from
a point near the speaker
terminals results in
lower impedance and
higher damping factor.
+
–
+ INPUT
Signal Sensing
NFB
NETWORK
+
NFB
NETWORK
–
NFB
NETWORK
- INPUT
+ Signal
Speaker Terminals
–
+
- GND
GND Sensing
Remote Sensing
Gain selector
Control circuit assembly
Parts selected for high sound quality and reliability
MOS-FET switches
Major parts in signal path are gold-plated
Low-Noise Instrumentation Amplifier Configuration and Further Refined MCS+ Topology
Low-noise instrumentation amplifier in discrete
configuration allows balanced signal paths
MCS+ (Multiple Circuit Summing) circuit in
amplifier section drastically improves S/N ratio
Current feedback principle provides excellent
phase characteristics in high frequency range
The balanced input stage circuitry features instrumentation amplifier topology such as used in high-precision
measuring equipment. This approach ensures perfectly
matched input conditions for the positive and negative
side of the signal and thereby allows the realization of
high-performance balanced signal transmission.
The input stage of the amplifier section features
another Accuphase innovation: MCS+ (Multiple
Circuit Summing). This innovative method further
reduces noise and at the same time helps to ensure
rock-stable performance.
As shown in the illustration, the M-6200 uses the
output signal current rather than voltage for
feedback. Since the impedance at the current
feedback point is very low, there is almost no phase
shift. A minimal amount of NFB therefore results in
maximum improvement of circuit parameters. The
principle provides excellent stability and is ideally
suited to power amplifiers that handle signals ranging
from extremely low to dynamic, high-volume levels.
Signal Input Stage
Power Amplifier Stage
+
8-PARALLEL
POWER
AMPLIFIER
+
–
–
NFB
NETWORK
+ INPUT
− INPUT
TRANS-IMPEDANCE
AMPLIFIER
OUTPUT
GAIN CONTROL
CIRCUIT
- INPUT
NFB
NETWORK
–
+
BUFFER
8-PARALLEL
POWER
AMPLIFIER
Low-Noise Instrumentation Amplifier Configuration
AMPLIFIER
CURRENT ADDER
+
‒
-V
CONVERTER
BUFFER
+ INPUT
CURRENT NFB
NETWORK
Principle of Current Feedback Amplifier
OUTPUT
Output Power Characteristics
1,300
Circuit Diagram of Power Amplification Circuitry
Signal Input Stage
1,250W
MCS+ (Multiple Circuit Summing)
1,200
1,100
1,000
Output power (W)
Q17
1,200W
Q25
Q5
800
755W
Q1
700
Q3
Q9
Q41
+ B1
Q45
Q49
Q18
Q13
Q26
Q53
Q57
Q61
Q65
Q69
Q73
Q77
Q81
Q34
BIAS
STABILIZER
8-PARALLEL PUSH-PULL
BIAS
STABILIZER
BIAS
STABILIZER
BIAS
STABILIZER
600
500
Q6
600W
410W
400
200
+ B2
Q33
+ B4
900
300
High-Power Transistors
+ B3
BIAS
STABILIZER
Q10
Q14
Q35
Q19
Q27
− B4
Q50
Q28
+ INPUT
211W
Max. output power
Rated output power
4Ω
2Ω
Q29
1Ω
Q7
Impedance (Ohms)
Q70
Q74
Q78
Q82
− B1
OUTPUT
+ B2
Q37
Q43
+ B1
Q47
+ B4
Q11
Q66
+ B3
BIAS
STABILIZER
Q21
Q62
− B3
+
– INPUT
Q58
− B2
−
DC SERVO
150W
8Ω
MAX
−3dB
−6dB
−12dB
GND
Q54
Q46
Q42
BIAS
STABILIZER
FEEDBACK
NETWORK
GAIN SELECTOR
300W
100
Q36
Q20
Q51
Q55
Q59
Q63
Q67
Q71
Q75
Q79
Q83
Q30
Q38
Q22
Q15
BIAS
STABILIZER
Q2
Q4
BIAS
STABILIZER
BIAS
STABILIZER
Q8
Q12
Q16
Q23
Q31
Q39
− B4
Q52
Q32
Q24
High-power transistors for audio applications
8-PARALLEL PUSH-PULL
BIAS
STABILIZER
BIAS
STABILIZER
Q40
Q56
Q60
Q64
Q68
Q72
Q76
Q80
Q84
Q48
− B1
Q44
− B2
− B3
Power Amplifier Assembly
Rear Panel Features
Output stage with 8-parallel push-pull power
arrangement of high-power transistors mounted
directly to large diecast aluminum heat sink,
also comprising MCS+ circuitry and current
feedback amplifier. Two completely identical
units arranged at left and right are used.
Operation selector allows
bridged operation of two
M-6200 units.
Phase selector accommodates
pin 2 ⊕ and pin 3 ⊕ type
balanced connections.
■ Using four M-6200 units, upgrading to bridged operation or bi-amping is possible.
■ Connect the input signal either to the balanced or the unbalanced inputs on all units.
Example for bridged connection
Example for bi-amping connection
Bridged operation of two M-6200 units allows upgrading
to a monophonic amplifier with even higher power.
Left speaker
Right speaker
− terminals to each other, use
* For connecting the SPEAKER
−
speaker cable of the same grade as for other speaker connections.
In a bi-amped setup, the speaker units for the LOW
frequency range and HIGH frequency range are driven by
separate amplifiers, for optimum sound quality.
Left speaker
* The speakers must have a built-in crossover network and
separate inputs for LOW and HIGH range.
* Operation selector of left channel/right channel q unit: NORMAL
* Set the operation selectors of all four units to NORMAL.
* Operation selector of left channel/right channel w unit: REVERSE
HIGH
Branch output
−
+
Right speaker
Branch output
− +
BALANCED
− +
LOW
HIGH
LOW
− +
BALANCED
LINE
L
L
R
R
Left-channel unit q
Left-channel unit w
LINE
L
L
R
R
Branch output
Left-channel unit w
Preamplifier
Preamplifier
LINE
Left-channel unit q
− +
− +
BALANCED
LINE
Branch output
− +
− +
BALANCED
Right-channel unit q
Right-channel unit w
Right-channel unit q
Front panel
q Hold time indicator
3 SEC / ∞
r Meter illumination/operation/
hold time selector
OFF / NORMAL / 3 SEC / ∞
w Power meter
Rear panel
(dB and % indication)
t Power switch
Right-channel unit w
e Input indicator
LINE / BALANCED
u Gain selector
-12dB / -6dB / -3dB / MAX
y Input selector button
LINE / BALANCED
i Inputs
LINE / BALANCED
o Speaker terminals
(One is used for signal pass-through)
!0 Operation selector
NORMAL / REVERSE
(Same output from both sets)
!1 Balanced input
phase selector
!2 AC power connector★
M-6200 Guaranteed Specifications
[Guaranteed specifications are measured according to EIA standard RS-490.]
● Continuous Average Output Power (20 - 20,000 Hz)
1,200 watts into 1 ohm
(1-ohm loads allowed with music signals only)
600 watts into 2 ohms
300 watts into 4 ohms
150 watts into 8 ohms
Bridged mode (2 units)
2,400 watts into 2 ohms
(2-ohm loads allowed with music signals only)
1,200 watts into 4 ohms
600 watts into 8 ohms
● Total Harmonic Distortion
0.05%
with a 2-ohm load
0.03%
with a 4 to 16-ohm load
● Intermodulation Distortion
0.01%
● Frequency Response
At rated continuous average output: 20 – 20,000 Hz +0 -0.2 dB
At 1 watt output:
0.5 – 160,000 Hz +0 -3.0 dB
● Gain 28.0 dB (GAIN selector in MAX position)
● Gain Selection -12 dB, -6 dB, -3 dB, MAX
● Output Load Impedance Continuous output: 2 to 16 ohms
With music signals: 1 to 16 ohms
● Damping Factor
1,000
● Input Sensitivity (with 8-ohm load)
1.38 V for rated continuous average output
0.11 V for 1 watt output
● Input Impedance
Balanced: 40 kilohms
Line:
20 kilohms
● Signal-to-Noise Ratio (A-weighted, with input shorted)
127 dB (GAIN selector in MAX position)
133 dB (GAIN selector in -12 dB position)
At rated continuous average output
● Output Level Meter
-40 dB to +3 dB (dB / % indication)
Logarithmic compression scale
Display illumination off switch
Peak hold time select: 3 seconds, ∞
● Power Requirements 120/220/230 V AC, 50/60 Hz
● Power Consumption
100 watts idle
575 watts in accordance with IEC 60065
● Maximum Dimensions Width: 465 mm (183.1")
Height: 220 mm (86.6")
Depth: 499 mm (196.5")
● Mass
40.2 kg (88.6 lbs) net
50.0 kg (110.2 lbs) in shipping carton
Remarks
★ This product is available in versions for 120/220/230 V AC. Make sure that the voltage shown on the rear panel matches the AC line voltage in your area.
★ 230 V version has an Eco Mode that switches power off after 120 minutes of inactivity.
★ The shape of the AC inlet and plug of the supplied power cord depends on the voltage rating and destination country.
Supplied accessory
● AC power cord
●
The specifications and appearance of this product are subject to change without notice.
5年間保証
D1505Y PRINTED IN JAPAN 850-2191-00(B1)
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