|150,000yen(around the 1981 time)
The Integrated Amplifier which pursued whether they were efficient-izing and
high output while harnessing the quality of Class-A operation.
to realize the almost same body size as the equivalent amplifier of Class B
operation with loading by Class-A power amplifier, the real bias circuit is
A real bias circuit is the same principle as POA-3000 or PMA-970, and the method of preceding bias current and making it recover from signal
current is used for it. As compared with the conventional system that this
supplies much bias current at the time of a non-signal, about 1/of power
consumption improvements of 10 are realized.
The circuit of the power
amplifier part is constituted from a low-noise FET parallel differential
amplification + direct direct-current servo and a pre-driver stage of the 3
steps of differential amplification current mirror cascode bootstrap output
which has powerful drive capability in the 2nd step by the first rank.
The real drive circuit is carried and the voltage at the time of speaker
real load and the phase difference of current are improved.
In this circuit,
it adds to parallel use of a power transistor paying attention to operation of
the amplifier at the time of speaker mounting,When the real drive line by an
electronic device is installed in a protection circuit, lack of the signal at
the time of the Taishin number is canceled and a common speaker system is
connected, near fo of the Oide power, distortion is improved about 1-/50.
The equalizer circuit consists of the NF type direct-current amplifier
and CR type equalizing filters by newly developed low-noise dual FET, and the
first rank is 4 parallel differential amplification circuit of direct
direct-current servo system dual FET, and is planning a low-noise and Quantity
Moreover, the cascode bootstrap circuit which does not receive the
influence of input impedance in the first rank of an equalizer is adopted, and
distortion is reduced.
The original direct direct-current servo circuit
where stability is high was carried, and capacitor removal is realized from all
the signal courses of resulting in SP output from MC input.
control part consists of only passive devices required for tone control, and has
the simple composition of having removed the mass capacitor harmful to sound
quality from the signal course, by including it in some power amplifier.
Moreover, it has the structure where the composition of a main circuit is
not affected at the time of a tone defeat, either.
toroidal transformer and a 44,000-micro F block capacitor are carried in the
Furthermore, in order to supply current to the
right-and-left channel of a power stage on the same conditions, the layout of a
power current pure radiation construction system is adopted, and shortening of
wiring is also attained.
Moreover, sufficient shield for the power
transformer circumference is given, and the influence on a signal system circuit
and the influence on external apparatus are suppressed.
protection circuit which served as muting operation at the time of power switch
ON is carried.
The headphone jack which carries the impedance change
function of High/Low is equipped.
The function of a Subsonic Filter,
loudness control and a muting function, a direct couple switch, etc. is carried.
The side wood of the Brazi LeAnn rosewood tone is attached to the side.
|<Power amplifier part>
||Direct direct-current servo system Denon
|Output power (both channel drive, a sine wave continuation output)
||80W+80W (8 ohms, 20Hz - 20kHz)
(4 ohms, 1kHz)
|THD (at the time of 60Hz:7kHz=4:1 and an
||0.004% or less
|Output bandwidth (IHF, both ch(es) drive)
||5Hz - 100kHz (THD 0.03%)
|Frequency response (at the time of 1W
||1Hz-250kHz+0 -3 dB
|Signal to noise ratio (IHF-A)
|Output load impedance
||0.1ohm or less
|<Preamplifier part (equalizer
||Phono1, 2 MM:2.5mV /, 47kohm
MC: 125 microvolts/100 ohms
Tuner, AUX, Tape1, 2:150mV/40kohm
|The maximum except take-off/Output power
||20Hz-100kHz±0.2dB (MM and MC)
||0.001% (1kHz, output 8 V:00)
|Signal to noise ratio (IHF-A, input short
||Phono1, 2 MM: 90dB
Phono1, 2 MC: 75dB
(at the time of a 250-microvolt input)
Tuner, AUX, Tape1, 2:110dB
||bass: ±8dB (100Hz)
treble: ±8dB (10kHz)
||18Hz, 6 dB/oct
||100Hz : +7dB, 10kHz : +6dB
|Power supply voltage
|Power consumption (Electrical Appliance and
Material Control Law)
||Width 470x height 140x depth of 410mm