|65,000yen(around the 1980 time)
The Integrated Amplifier which carries a super equalizer and a real drive
Not only at MM cartridge but at the time of MC cartridge use,
it has the composition of having removed the capacitor from all the stages of
the signal course from the Phono input terminal to the speaker output terminal.
It had realized by adopting the direct direct-current servo circuit carried
also in PMA-970, and perfect Capacitor-Less composition shut out direct-current
drift effectively, and has secured super-low-pass stability.
equalizer by which the combination was carried out in each merit of NF form
(returned type) and CR form (unreturned type) is carried in the equalizer
amplifier part, and outstanding RIAA deflection is realized.
of a super equalizer consists of the NF form direct-current amplifier and CR
form equalizing filter by low noise dual FET,The first rank considered it as the
parallel differential amplification of dual FET of a direct direct-current servo
system, and it has canceled direct-current temperature drift, improving S/N and
A real drive circuit is carried and reduction of the
distortion is aimed at.
Paying attention to operation of the amplifier at
the time of speaker mounting, this circuit is the technology in which distortion
of the amplifier at the time of reactive load was reduced, also in the time of
high power, realized the good characteristic and has realized low
The circuit composition of the power amplifier part is 3 "a stage
differential pre-driver + Darlington connection complimentary push pull
output stage" of "two steps of first rank low noise FET differential
direct direct-current servo system + transistor differential."
Furthermore, the thing which you carry the zero crossing linear bias
circuit, and is made to build in a high speed thermal feedback circuit,While
developing the merit of non switching further and attaining stabilization of
quick bias from the time of a power-source injection, high stability was
realized to external factors, such as a temperature change and time progress, and not only banishment of switching distortion but reduction of crossover
distortion is realized.
The real-time tone control circuit is carried in
the tone circuit.
This circuit consisted only of a passive device required
for tone control, is including it in some power amplifier, and has removed the
mass capacitor harmful to sound quality from the signal course.
power-source part consists of the power transformers and the 30,000-micro F
block capacitors which gave the multiplex shield.
In order to reduce
magnetic material as much as possible, L angle and an aluminum radiator are
combined and the core of amplifier is summarized shapely.
merit of a simple circuit, such as operating an input change part by remote
control, and shortening a signal course sharply, is raised.
couple switch is carried.
The Rec out off function to remove the
influence on sound quality is begun, and a Subsonic Filter and loudness control
|<Power amplifier part (Tuner in->SP
(both channel drive, a sine wave continuation output, 20Hz - 20kHz)
|THD (20Hz - 20kHz, Output-power-3dB)
||0.007% or less
|Cross modulation distortion (an equivalent
for 60Hz:7kHz=4:1 and an Output power)
||0.005% or less
|Output bandwidth (IHF, both ch(es) drive)
||4Hz - 100kHz (THD0.1%)
|Frequency response (at the time of 1W
||1.5Hz-250kHz+0 -3 dB
|Output load impedance (1kHz)
||AorB: 4ohms - 16ohms
|<Preamplifier part (Input
sensitivity/impedance is removed and it is Phono in->Rec out)>
||Phono MM: 2.5mV/50kohm
Tuner, AUX, Tape:150mV/40kohm
|The maximum except take-off/Output power
|RIAA deflection (MM, MC)
|THD (at the time of 1kHz and 6V output)
||0.002% or less
|Signal to noise ratio (IHF-A, input short
||Phono MM: 88dB (at the time of a 2.5mV
Phono MC: 72dB (at the time of a 0.25mV input)
Tuner, AUX, Tape:
||Bass: ±8dB (100Hz)
Treble: ±8dB (10kHz)
||18Hz, 6 dB/oct
||100Hz : +7.5dB, 10kHz : +5.5dB
|Power supply voltage
|Power consumption (Electrical Appliance and
Material Control Law)
||Width 434x height 112x depth of 390mm