|69,800yen(around the 1981 time)
The amplifier which realized dynamic distortion 0 unreturned [ of 0dB ], and the
Integrated Amplifier which carries a super-broadband super equalizer.
Circuit composition consists of a real drive circuit, amplifier of a direct
DS system which carries a direct A system unreturned [ of 0dB ], and a
MC/MM super equalizer.
This basic circuit has the same composition as PMA-770 which is an upper model.
Furthermore, one has adopted as all the signal courses of a speaker output
terminal the Capacitor-Less composition between which it is not placed
by the coupling capacitor from MC input terminal.
The MC/MM super equalizer
is carried and the broadband characteristic of 20Hz-100kHz}0.2dB is realized.
Composition consists of the NF form direct-current amplifier and CR form
equalizing filter by newly developed low noise dual FET, and the first rank
serves as dual FET differential amplification of the direct direct-current servo
The power amplifier part has adopted the amplifier unreturned [
of 0dB ].
By this system, static distortion produced by the magnification
characteristic that a power transistor is non-linear is driven in to the domain
of zero according to the effect of a direct DS circuit, and high-quality
sound-ization is attained.
Circuit composition was used as the 3 steps of differential current mirror
by first rank low noise FET, by the complimentary emitter-follower, attained
low impedance-ization and has separated it completely with the electric
power magnification stage. High speed-ization of a signal is realized,
while using an electric power magnification stage as the push pull output
stage by a high-speed power transistor and aiming at improvement in each
A zero crossing linear bias circuit original with DENON
is carried in an output stage, generating of the switching distortion by cutoff
of a power transistor is banished, and the quality of Class-A amplifier and
efficient and high-output coexistence of Class B amplifier are aimed at.
The real drive circuit which reduces distorted generating of the amplifier at the time of speaker mounting is carried.
Thereby, by the load
resistance of the speaker which changes with frequency, phase difference arises
between voltage and current, it stops having made distortion increase, and
distortion is reduced to 50 by about 1/near speaker fo.
in a chassis is considering it as the layout which separated each section of
equalizer amplifier and power amplifier, and is suppressing the mutual
Tone control, the Subsonic Filter, the loudness control
switch, and the Rec out selector are carried.
Moreover, the direct couple
switch and the mode switch in which a stereo reverse monophonic play is possible are carried.
The high-speed protection circuit is built in.
|<Power amplifier part>
||Unreturned [ of 0dB ] power amplifier system
(both channel drive, a sine wave continuation output, 20Hz - 20kHz)
|THD (20Hz - 20kHz, Output-power-3dB o'clock)
||0.005% or less
|Cross modulation distortion
(at the time of a 60Hz:7kHz=4:1 and Output-power equivalent amplitude
|0.002% or less
|Output bandwidth (IHF, both ch(es) drive,
||5Hz - 100kHz
|Frequency response (at the time of 1W
||1Hz-250kHz+0 -3 dB
|Output load impedance (1kHz)
||Speaker AorB: 4ohms - 16ohms
Headphone: 310mW/eight ohms
|<Preamplifier part (Input
sensitivity/impedance is removed and it is Phono in ->Rec out)>
||The super equalizer system by a direct
||Phono MM: 2.5mV/47kohm
Tuner, Aux, Tape:150mV/47kohm
|The maximum except take-off/Output power
|RIAA deflection (MC/MM)
||0.002% or less (at the time of 1kHz and 8V
|Signal to noise ratio (IHF-A, input short
Aux, Tape: 110dB (at the time of a 150mV input)
||Bass: }8dB (100Hz)
Treble: }8dB (10kHz)
||18Hz, 6 dB/oct
||Low-pass: +7dB (100Hz)
High region: +6dB
|Power consumption (Electrical Appliance and
Material Control Law)
||Width 434x height 132x depth of 407mm