|59,800yen(around the 1980 time)
The integrated DC Integrated Amplifier which adopted
the new class A scheme by a synchro bias circuit original with Technics.
It is an output stage by the side of - which has stopped the amplification action by the new class A amplification scheme when the signal by
the side of + enters,Moreover, the fixed bias current was given to the output
stage by the side of + to the signal by the side of -, it was not concerned with
the presence or absence of a signal, but the output stage was always set to the active state, and switching distortion is banished by considering a transistor
as a non cut-off.
Furthermore, since the high-speed response diode which an
output transistor saves the always suitable operating point, and switches a wave
since the signal path and the bias current have been independent has the
synthetic transfer characteristics near the square-law characteristics of an
ideal, crossover distortion has also been canceled.
DC amplifier has
adopted straight the straight DC scheme which amplifies a signal from a
high-level input or subsequent ones. This realizes the faithful
waveform-transmission property to a direct-current region, and the swing and the
phase frequency characteristic of the audio frequency band are made still the
The Dual FET of the one chip which was excellent in especially the temperature
characteristic is adopted as the first stage of a main amplifier.
By -10 degree-C-+50 degree C normal operation, DC drift is also set to
}10mV or less, and is suppressed on the conventional about 1-/5& relative-minimum
The differential amplifier by a low-noise Dual
FET is adopted as the phone equalizer circuitry first rank.
Since man month-MC is made into the interrupt-control-logic equalizer which
banished the input capacitor by adoption of Since man month-MC is made
into the interrupt-control-logic equalizer which banished the input capacitor
by adoption of FET,When an operational mode is set to straight DC, simple
circuitry called one coupling capacitor (output capacitor of an equalizer)
is realized from a phone input before a speaker termination.
High gain IC (100dB or more) is adopted as the phone equalizer following
stage, and the man-month right-and-left MC gain system for change-over is
conjointly realized with adoption of FET of a very low noise. Thereby, MC
cartridge can use it direct.
The concentrated power block which
suppresses the distorted occurrence by electromagnetic induction is adopted.
By adoption of this block, a power-source part and an output transistor are
unified, it connects with the shortest distance, and the distortion of the high
region by electromagnetic waves is suppressed on the minimum level.
Right-and-left standalone version 2 power source which achieved right-and-left
both channel independency of a rectification and the smoothing circuit
The highly efficient transformer which the power
transformer also made the coil float in a special resin, and stored it to the
shielding case is adopted, and there is little harmful equipment oscillation and
it serves as a high transformer of the shielding effect.
FET is adopted
as the load intensity of the error detector of a constant-voltage regulated
power supply, and the stable voltage with a high ripple (alternating-current
component) elimination factor leading to a harmful hum noise is supplied to the
voltage amplification stage to the main-amplifier first rank.
If a load
impedance is set to 2.2ohms or less, the load-intensity detection type
protection network which suppresses the electric current which flows into power
IC will be adopted. Furthermore, if DC component beyond }3V comes out, DC
detection type protection network which a relay works and separates a speaker is
If a cause is canceled, the auto return of both the circuitries
will be carried out to a normal operation.
Leading about of a product
line was minimum-ized and the remote action switchpoint which suppresses a
property failure is adopted as a Rec selector, an input selector, and a phone
The type by which a defeet is carried out at the middle point
is adopted as a tone control.
||Integrated DC amplifier
|<Tuner, the Aux->SP out
|Effective output (20Hz - 20kHz)
||70W+70W (8 ohms, 0.007%)
||0.005% (Output-power-3dB, 20Hz - 20kHz)
|Power bandwidth (THD 0.02%)
||5Hz - 100kHz
|Frequency characteristic (straight DC)
||20Hz-20kHz+0 -0.1 dB
|SN ratio (IHF-A, straight DC)
|Remains noise (straight DC)
|Dumping factor (8ohms)
||main or remote: 4ohms - 16ohms
remote: 8ohms - 16ohms
||Phono man month: 2.5mV / 47kohm
MC: 170 microvolts/47 ohms
Tuner, Aux, Tape:150mV /, 47kohm
|SN ratio (IHF-A)
MC: 68dB (250-microvolt input)
||20Hz - 20kHz, RIAA}0.5dB
||Bass: }10dB (50Hz)
Treble: }10dB (20kHz)
||20Hz-12dB / oct
|A high filter
||7kHz-6dB / oct
||+ 7dB (50Hz, Volume-30dB)
||Width 430x height 153x depth of 351mm