
Accuphase E-405 |
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350,000 yen(October, 1989 release) |
The Integrated Amplifier which union-ized the preamplifier and power
amplifier which became independent substantially, and constituted them that the
limit of an Integrated Amplifier should be overthrown.
The output stage of a power amplifier part has 5-parallel push pull composition
by ten output elements, and each element can adopt the thing of Pc(collector
loss)130W, and can send out sufficient power also to low load.
In the drive stage which
drives an output stage, while having adopted the two-step dregs cord direct
connection circuit of a dregs cord push pull and a MOS FET dregs cord push pull
and improving the high region characteristic by dregs cord connection, the
distortion at the time of the Koide power is suppressed few by MOS FET.
All the magnification stages also including a preamplifier part consist
of direct connection systems. Moreover, it has the changeover switch and input
terminal for separating the Puri part and a power part and using it as
independent amplifier.
Since there is a possibility that it may be amplified
as it is, a big direct current may appear in an output, and a speaker may be
damaged when direct-current voltage is impressed for a certain reason in that
case, the unnecessary direct-current ingredient was cut and "direct-current
servo system" has been adopted that direct-current drift of the amplifier by a
temperature change itself should be stabilized.
The direct-current voltage
which appeared in the output is detected, and the state of direct-current
voltage zero is maintained by returning to an input.
As a function of a
power amplifier part, the large-sized power meter which can supervise an Output
voltage is equipped.
Output electric power can be supervised in the
logarithm compression type peak meter arranged in the center of a panel.
Two speaker outputs are carried and it is controlled by large-sized
relay, and with an A+B output, two lines become parallel and it can respond also
to the bi-wiring which separated low-pitched sound and an inside loud-sound
network.
In the high level flat amplifier of a preamplifier part into
which the usual signals other than an analog disc are inputtedThe dregs cord
bootstrap differential system constituted with low noise dual FET and a
transistor is adopted, and the Miller effect distortion by the impedance of
input apparatus or change of volume control volume is prevented simultaneously
with high S/N.
Moreover, the XLR type balance connector is carried.
The equalizer amplifier equipped with the input circuit in consideration
of the characteristic of the cartridge of each MM type / MC model for exclusive
use is carried.
At the time of MM input, FET and the transistor which can
maintain high input impedance over all the frequency bands constitute the dregs
cord bootstrap difference input circuit in consideration of the Output voltage
of MM cartridge and an Output load impedance being high.
On the other hand, at the time of MC input, since signal voltage is low and the S/N improvement is
a primary importance theme, the dregs cord bootstrap difference input circuit
which selected carefully and uses an element with little peculiar noise is
constituted.
These changes were performed by the relay 1 and the relay 2, and the amplification degree which suited MM/MC simultaneously is chosen.
The power-source part which became independent of power amplifier
completely is carried in the preamplifier part.
After it is using Troy Dahl
Torrance of the low leakage flux for a power transformer and a high-speed diode
rectifies, stabilization is attained by ± dual tracking series regulator.
Since a straight signal course is constituted at the shortest, a relay
is installed in the place of a required signal course, and it is changing by a
change adopting the logic relay control system which controls these relays
electronically.
The encapsulated type relay developed as an object for
audios is adopted especially as a relay. A contact is a crossbar twin system and
has become low contact resistance and a thing of high durability.
An input change is a system which changes a relay electronically, only
presupposed that it is to control a logic circuit by a commander, and has
adopted the system which volume control also makes rotate a motor for manual
volume so that sound quality degradation may not occur.
The tone control for which the added type
filter was applied to tone control is developed and carried, and the influence
on the characteristic or sound quality is further eliminated by adopting the
quality element focused on sound quality.
Furthermore, an ON-OFF switch is
formed, and at the time of OFF, it constitutes so that a circuit may be passed.
It passes straight, an original flat signal makes the characteristic if
needed, and the principle of this circuit serves as a system of making it adjust
from a flat signal.
Operation of recording etc. is also possible in FM,
carrying the recording selector independently with the input selector, and
hearing CD.
Moreover, dubbing between recorders and the copy switch made
independently are carried.
The function of the Subsonic Filter which
cuts super-low-pass noises which mix a sound on either side, such as a mode
switch and an analog disc, the Compensation switch which reinforces the feeling
of low-pitched sound at the time of small volume, a headphone jack, etc. is
carried.
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.JPG) |
Form |
Integrated stereo Integrated Amplifier
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Continuation average output
(Bothchannel operation, 20Hz - 20kHz, 0.02% of distortion) |
4ohm load: 250 W/ch
8ohm load: 170 W/ch
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THD
(Both v operation, 0.25W - a continuation output, 20Hz - 20kHz) |
0.02% (4-16-ohm load) |
IM distortion |
0.01% |
Frequency response |
Main Amp Input: |
20Hz-20000Hz+0 -0.2dB (at the time of an
Output power)
0.5Hz-150000Hz+0 -3.0dB (at the time of 1W output)
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High Level Input: |
20Hz-20000Hz+0 -0.2dB (at the time of an
Output power) |
Low Level Input: |
20Hz-20000Hz+0.2 -0.5dB (at the time of an
Output power) |
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Dumping factor |
150 (8-ohm load, 50Hz) |
A rated input / input impedance |
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Input sensitivity
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Impedance
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At the time of an Output power
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EIA (at the time of 1W output)
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AD Input(MC): |
0.14mV |
0.011mV |
100ohms |
AD Input(MM): |
4.38mV |
0.335mV |
47kohm |
High Level Input: |
143mV |
10.8mV |
20kohm |
Balanced Input: |
143mV |
10.8mV |
40kohm |
Main Amp(unbal): |
1.47V |
110mV |
20kohm |
Main Input(bal): |
1.47V |
110mV |
40kohm
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The disc maximum input (1kHz, 0.005% of
distortion) |
MM input: 300mVrms (Rec Out)
MC input:
9.5mVrms (Rec Out) |
An Output power/Output load impedance
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Pre Output: 1.47V/200 ohm
Tape Rec
Output: 143mV/200 ohms (AD)
Headphones: 0.36V, conformity impedance 4-100ohm
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Gain |
Main Input -> Output: 28dB
High Level
Input -> Pre Output: 20dB
AD Input (MM) -> Tape Rec Output: 30dB
AD Input (MC) -> Tape Rec Output: 60dB |
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 a rated input
S/N |
Input conversion noise
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Main Amp Input: |
124dB |
-121dBV |
102dB |
High Level Input: |
110dB |
-127dBV |
83dB |
Balanced Input: |
98dB |
-115dBV |
83dB |
AD Input(MM): |
89dB |
-137dBV |
80dB |
AD Input(MC): |
74dB |
-150dBV |
78dB
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Tone control |
Low-pitched sound: Turnover frequency 300Hz,
±10dB (50Hz)
Loud sound: Turnover frequency 3kHz, ±10dB (20kHz)
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Loudness Compensation (Volume-30dB)
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+6dB(100Hz) |
Subsonic Filter |
17Hz, -12 dB/oct |
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 |
4-16ohm |
The semiconductor used |
Transistor: 85 pieces
FET: 22 pieces
IC: 30 pieces
Diode: 65 pieces |
Power source |
100V/117V/220V/240V, 50Hz/60Hz
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Power consumption |
At the time of no inputting: 90W
Electrical Appliance and Material Control Law: 390W
At the time of an
8ohm load Output power: 620W |
Dimensions |
the width 475x height 180(piece -- it
includeds) x depth of 375mm |
Weight |
25kg |
Attachment: Remote commander RC-3
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Remote control system |
Infrared pulse system |
Power source |
DC 3V |
Battery |
SUM-3 (an IEC name, R6), two pieces
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The maximum Dimensions |
Width 64x height 149x depth of 18mm
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Weight |
140g (Battery includeds) |
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