The stereo Integrated Amplifier which carrying the power amplifier unreturned [
of 0dB ] etc. inherited the technology of PMA-790, and was developed.
The power amplifier which eliminated the negative return loop unreturned
[ of 0dB ] is carried.
This system is a thing adapting the technology
developed by POA-8000 in which it does not return, and has structure using a
direct distortion servo circuit. A direct distortion servo circuit compares the
signal (main signal + distorted ingredient) and incoming signal which are acquired from the output side, detects only a distorted ingredient, then carries
out phase inversion of this distorted ingredient, and is adding it to the input
Static distortion is driven into the domain of zero by this operation.
Moreover, the noise which appears in the output side of amplifier was also
regarded as a difference with an incoming signal, and is removed. [ as well as a
distorted ingredient ]
Since there is no feedback of a signal and time delay
does not arise by this, dynamic distortion which affects the Hearing impression
quality is suppressed. Moreover, in order that there may be no NFB circuit, it
is not influenced by the back electromotive force from a speaker, but the
distorted increase and generating at the time of speaker connection are
The power transistor of Pc200W is adopted as a power
amplifier part final stage. Furthermore, the quality of a Class-A and efficient
coexistence of Class B are aimed at with the direct Class-A amplifier system.
The perfect direct-current composition which does not use a coupling
capacitor for all the signal courses from the input terminal for MC cartridges
to a speaker output terminal is adopted.
The large-sized toroidal
transformer of 260VA, the mass capacitor of 30,000microf, the first recovery
diode of the high-speed rectification which reduced switching distortion, etc.
are adopted as a power-source part.
The super equalizer is adopted as an
equalizer part in order to pull out the engine performance of MC cartridge.
This has attained RIAA deflection 20Hz-100kHz}0.2dB.
and a high-speed protection circuit are carried.
|<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)
||0.003% or less
|Cross modulation distortion
(at the time of a 60Hz:7kHz=4:1 and Output-power equivalent amplitude
|0.002% or less
||Below a measurement limit
||}300v/microsecond or more
|Output bandwidth (IHF, both channel drive)
||5Hz - 80kHz (THD 0.025%)
|Frequency response (at the time of 1W
||1Hz-250kHz+0 -3 dB
|Output load impedance (1kHz)
||Speaker AorB: 6ohms - 16ohms
Headphone: 490mW/eight ohms
||Super equalizer system
||Phono MM: 2.5mV/47kohm
Tuner, DAD/Aux, Tape:150mV/47kohm
|The maximum except take-off/Output power
|RIAA deflection (MC)
|THD (at the time of 1kHz and 8V output)
||0.002% or less
|Signal to noise ratio (IHF-A, input short
||Phono MM: 87dB (at the time of a 2.5mV
Phono MC: 70dB (at the time of a 0.25mV input)
Tape: 110dB (at the time of a 150mV input)
||Bass: }8dB (50Hz/100Hz)
||20Hz, 6 dB/oct
||Low-pass: +7dB (100Hz)
High region: +6dB
|Power consumption (Electrical Appliance and
Material Control Law)
|Dimensions (a base, a knob, a terminal
||Width 470x height 132x depth of 413mm