
Accuphase E-407 |
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400,000 yen(October, 1999 release) |
The Integrated Amplifier of the new reference model which supplied the design
technique, the newest circuit, and quality element which the Accuphase
cultivated, and was developed aiming at the highest peak of an Integrated
Amplifier.
The power transistor for multi-emitter type large electric
power audios excellent in many characteristics, such as the high frequency
characteristic, a current gain linearity, and switching, is adopted as an output
element.
This element is constituted from a 3 parallel push pull, low
impedance-ization is attained, and effective heat dissipation processing is
carried out by fixing on a large-sized heat sink.
The preamplifier part
/ power amplifier part has adopted the current feedback magnification circuit
which was excellent in the high region characteristic.
This circuit lowers
the impedance of the input terminal by the side of a return first, detects
current, carries out I-V (current-voltage) conversion of that current with a
transformer impedance amplifier, and is making the output signal. In this
circuit, since the impedance of a return input portion is very low, it is hard
to generate phase rotation and there is almost no necessity for a phase
guarantee.
For this reason, since many characteristics are sharply improvable by a
little NFB, it excelled in dynamic characteristics, such as a standup,
and the natural energy response has been obtained also in respect of sound
quality.
The line amplifier part consists of discrete parts by a
current feedback magnification circuit.
Foundations are the differential
pure complimentary push pulls which are the original of an Accuphase, prepare a
single ended push pull type emitter follower in an output stage, and are
constituted comparatively simply.
Thereby, phase compensation of each stage
is also light and the sound quality improvement is aimed at.
Since a
straight signal course is constituted at the shortest, the logic relay control
system which controls a relay electronically has been adopted.
The sealed
type for communication industry was adopted as the relay used for this, and low
contact resistance and quantity durability are realized by making a contact into
a plated with gold and a crossover twin system.
The added type active
filter system is adopted as tone control.
It passes straight, and if needed,
this system is another, makes the characteristic, and is making the original
flat signal adjust it from a flat signal.
The large-sized Troy Dahl type
transformer of the large power capacity of about 600 VA(s) is carried in the
power-source part, and also it excels in heat conduction, and using the high
load material of the vibrationproofing effect, it adheres to the aluminum case
of efficient heat dissipation structure, and the influence on the exterior is
intercepted.
In order that a toroidal transformer may coil thick copper wire around a doughnut-like core,Since it is small, and the toroidal transformer of
the Max ring type is adopted as E-407 in which conversion efficiency has the
features, like it is high, the section of an iron core is [ impedance is very
low, ] close to a circle and adhesion nature of a coil is closely good
circularly,A loss can make weight light few, and the leakage flux is small and
makes a roar and vibration smaller. Furthermore, iron loss and in rushes current
are small suppressed by enlarging the rate of a bulk density of copper wire for
the cross-sectional area of an iron core small.
Moreover, two 33,000-micro F
things are carried in the aluminum electrolytic capacitor for filters.
The amplifier only for headphone is formed and consideration is carried
out to the sound quality of headphone.
It is possible to cut the output to a
speaker with a speaker selector, and to carry out variable [ of the headphone
output ] in main volume.
It is begun to delete brass Naked material in a
speaker terminal, it is formed into a golden plate in it, and the large-sized
speaker terminal which can respond also to a thick cable is carried in it.
Two speaker outputs are carried and the use to change and bi-wiring
connection are possible.
The logarithm compression type analog type
large-sized peak power meter is carried.
This meter also carries the on/off switch of lighting.
Two balance inputs are carried.
The separate
switch and input-and-output terminal which can carry out independent use of a
preamplifier and the power amplifier are carried.
The remote commander
in whom operation of volume and an input change are possible is attached.
The slot for option boards is carried and it can extend on the board of
an AAB standard (Accuphase Analog Bus) standard according to a use.
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.JPG) |
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Form |
Integrated stereo amplifier
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Rated continuation average output
(Both channel operation, 20Hz - 20kHz) |
260 W/ch (4ohms)
220 W/ch (6ohms)
180 W/ch (8ohms) |
THD (both channel operation) |
0.02% (4ohms - 16-ohm load)
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IM distortion |
0.01% |
Frequency response |
High Level input, Main input :
20Hz-20kHz+0 -0.2 dB (at the time of a rated continuation average output)
2Hz-150kHz+0 -3.0dB (at the time of 1W output) |
Dumping factor |
120 (8-ohm load, 50Hz) |
Input sensitivity/impedance
(An Output
power / EIA1W output) |
High Level input: 158mV/11.2mV/20kohm
Balanced input: 158mV/11.2mV/40kohm
Main input: 1.58V/112mV/20kohm
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An Output voltage/impedance |
Pre output: 1.58V/50 ohm (at the time of a
rated continuation output) |
Gain |
High Level input -> Pre output: 20dB
Main input -> output: 28dB |
S/N, input conversion noise |
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Input short-circuit
and A-compensation |
EIA S/N
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At the time of an Output power
S/N |
Input conversion noise
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High Level input: |
113dB |
-130dBV |
82dB |
Balanced input: |
92dB |
-108dBV |
82dB |
Main input: |
128dB |
-124dBV |
103dB
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Tone control |
Low-pitched sound (300Hz): ±10dB (50Hz)
Loud sound (3kHz): ±10dB (20kHz) |
Loudness Compensation |
+ 6dB (100Hz, Volume-30dB) |
Attenuator |
-20dB |
Power meter |
Logarithm compression type peak level
display
dB scale and the output Direct reading at the time of 8-ohm load
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Load impedance |
4ohm-16ohm |
Headphone jack |
Conformity impedance: 4ohms - 100ohms
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Power source |
AC100V, 50Hz/60Hz |
Power consumption |
45W (at the time of no inputting)
410W
(Electrical Appliance and Material Control Law)
605W (at the time of an
8-ohm load Output power) |
The maximum Dimensions |
Width 475x height 180x depth of 423mm
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Weight |
23.7kg |
Attachment: Remote commander RC-20
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Remote control system |
Infrared pulse system |
Power source |
DC 3V |
Battery |
AA -- type and two pieces |
The maximum Dimensions |
Width 55x height 194x depth of 18mm
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Weight |
100g (Battery includeded) |
Option: Option board |
With no picture
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Line-in board Line-9 (6,000yen) |
The common high-level input terminal of
an imbalanced system.
Analog signals, such as CD player and a tuner, are
played.
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With no picture
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Analog disc input board AD-9 (30,000yen) |
All cartridges are supported by loading
of a high gain equalizer.
With an internal DIP switch, a MM/MC change, MC
input impedance, and Subsonic-Filter on/off can be set up.
MM |
Gain: 36dB
Input impedance: 47kohm
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MC |
Gain: 62dB
Input impedance: 10, a 30 or
100-ohm change |
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Line-in board Line-10 (8,000yen) |
The common high-level input terminal of
an imbalanced system.
Analog signals, such as CD player and a tuner, are
played. |
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Analog disc input board AD-10 (50,000yen) |
All cartridges are supported by loading
of a highly efficient high gain equalizer.
With an internal DIP switch, a
MM/MC change, MC input impedance, and Subsonic-Filter on/off can be set up.
MM |
Gain: 29dB
Input impedance: 47kohm
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MC |
Gain: 60dB
Input impedance: 10, a 30 or
100-ohm change |
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