|250,000yen(November, 1981 release)
The Integrated Amplifier which carries a DUObeta
circuit / S.
In addition to the power source plusX of the DUObeta
circuit which combined "proper-quantity NFB" and "DC servo", and a control
feedback of tone-quality dominance, the DUObeta circuit / S which furthermore, added "one-step amplification amplifier" are developed, and it carries in the
equalizer and the power part.
One-step amplification amplifier has adopted
FET for MC head amplifier as the first rank, and has the structure of taking out
gain required for high gm and this FET of a low-noise by sending the large
current of 7mA per one stone from the first.
After making an output stage
become independent completely so that it can come, simultaneously there may be
no influence in the first rank, the 2nd step is removed, and the voltage amplification has realized the ideal circuitry only of one step.
output unit is the intrinsic Class-A operation which fixes a bias current, and
has realized Oide power of 50 W/ch.
In a lot of exothermics by Class-A
operation, it corresponds by two large-sized heat pipes, and this heat pipe is
considering it as a symmetric figure, and has banished heat-dissipation sound.
One-step amplification amplifier is adopted also as a head amplifier
The low-noise is realized making the very low PNP transistor of input
equivalent resistance into a single differential at the first rank, and
obtaining sufficient gain.
An input selector, light filters, a
monophonic switchpoint, a balance control, etc. are separated at the time of a
disk play, and the phone straight functionality which links an equalizer and
power amplifier directly is carried.
Since sound-recording frequencies,
such as a disk, may be rising gently toward a high region or may be descending
conversely, such a peculiarity is rectified and the linear equalizer which
returns recording characteristics to a flat is carried.
A high region
and low-pass one carry the tone control which can choose nine turnover
It is the design which thought as important the frequency which
begins a transition rather than the variation, and the Lux scheme NF type tone
control from which a gentle transition property is acquired is adopted.
The capacity of 400VA was given to the power-source part using the requests-for-price-quotations
EI core, and the power transformer which hardened the interior by silica
sand and suppressed the temperature rise is adopted as it.
Moreover, the thing with a capacity of 30,000 micro F is employed full time as an electrolytic capacitor two times by 99.99% of an aluminum purity, and
ending with a tone-quality measure.
The Puri heating functionality is
carried, and a small-quantity electric current can be sent and warmed.
The warmup indicator is carried and it can check having gone into
The line phase sensor is carried, the polarity of
the AC power source of an it1 is detected, and a tone-quality mandatory is
||50W+50W (a Class-A operation, 8 ohms, both channel operation)
||0.005% or less (8 ohms, both channel operation, -3dB)
Phono MC: 80 microvolts
Tuner, AUX, Monitor, Main In: 220mV
||Phono man month: 100kohm, 50kohm,
Phono MC: 300 ohms, 100ohm, 40ohm
Tuner, AUX, Monitor:40kohm
Main In: 47kohm
|SN ratio (IHF-A)
Phono MC: 80dB
Tuner, AUX, Monitor, Main In: 110dB
||10Hz - -100kHz one dB
||Low-pass turnover: 55Hz, 77Hz, 110Hz, 155Hz,
220Hz, 310Hz, 440Hz, 620Hz, 820Hz
High region turnover: 620Hz, 880Hz,
1.2kHz, 1.7kHz, 2.5kHz, 3.5kHz, 5kHz, 7kHz, 10kHz
The maximum variation:
||Three lines (Tape1, 2, Tape Front)
||Four lines (1->2, 2->1, 1 ->Front,
||up tilt, down tilt: Two steps each (one step
||Width 453x height 174x depth of 460mm