||89,800yen(around the 1987 time)
The Integrated Amplifier which carries a digital
4DACs and 18-bit conversion system are adopted as a
In 4DACs and 18-bit conversion system, two digital
analog converters which carry out the independent process of + component and -
component of an input signal are carried in each channel of L/R, and it is
considered as 4DAC conversion system which uses a total of four digital analog
converters. In this circuitry, first, by newly developed 4DAC processor LSI, the
signal of + and - is distinguished out of the inputted digital signal, two
digital analog converters are switched and the high-speed treatment of these
signals is carried out. The D-A conversion which zero cross distortion does not
generate theoretically by this is realized.
Moreover, adoption of 4DAC
processor LSI etc. has realized an 18-bit operation of a digital analog
converter in the mean-value music level not more than -12dB. This has acquired
analog signal waveform regeneration capacity with more faithful adoption and
interval of the digital filter of a 4 time oversampling 18bit scheme.
With the automatic switching scheme, the sampling frequency supports
three kinds, 32kHz, 44.1kHz, and 48kHz, and supports a compact disk player, DAT, and a BS tuner.
The digital input carries two lines, light and a
The classAA amplifier of a VC-4 amplifier (Voltage Current 4
amplifier system) stream composition is carried in the power amplifier part.
In this circuitry, in each ch of L/R, voltage control amplifier is released
from the current supply source, and voltage control very faithful to an input
signal is realized by making separate amplifier take charge of voltage control
and an electric-current drive. Moreover, electric-current drive amplifier has
acquired sufficient current-supply-source capacity for a speaker drive.
The power transformer with which the high-density efficient technology
by an OFC line full sort coil method was used is carried in the power-source
Moreover, the newly developed high speed EX electrolytic capacitor is
adopted as the electrolytic capacitor for power sources. By application of
biotechnology, this capacitor is improving the purity of the electrolytic
solution double or more figures, and has also canceled the slight distortion by
the impurity adhering to an electrode.
loading s The power amplifier
direct functionality in which compact-disk direct functionality was developed
having inputted directly the power amplifier direct input signal
and the built-in digital-analog-converter output signal into power amplifier
only through a classAA buffer and a power amplifier input volume in this
functionality -- high -- the purity amplification is enabled. Having adopted the
P.C.L. low-impedance volume as the power amplifier input volume and an interval
have realized an SN ratio modification effect of about 10dB.
performance analysis and audition which were put into practice also among the
selection of the audio peculiar part are carrying out the careful selection
using of high purity OCC and the OFC material at an in-use cage, an internal
wiring, or the lead wire of each part.
In order to reduce the
tone-quality failure by oscillation of amplifier, measures against vibration
proof, such as a large-sized metals insulator, are taken.
In order to
prevent a digital circuit, a phone equalizer circuitry, and a power amplifier
circuitry interfering mutually, each block is shielded severely. Furthermore,
thorough exclusion of the tone-quality failure by the interference between the
sources is carried out with adoption of the active servo power supply which
eliminates the interference which leads a power source.
|The rear panel of SU-V 90D equipped with the input terminal with abundant
includeds for the optical link
|The internal structure of SU-V 90D
|(Above) OCC cross-section system
(Below) Conventional material cross-section system
|classAA conceptual diagram
|The block diagram of a power amplifier direct
|(Left) High speed capacitor
(Right) The conventional electrolytic capacitor
|Effective output (20Hz - 20kHz)
||120W+120W (6 ohms, 0.005%)
||0.002% (Output-power-3dB, 20Hz - 20kHz)
||20Hz-20kHz+0 -0.2 dB
||115dB (at the time of IHF'66 and Power Amp
||main or remote: 6ohms - 16ohms
||Phono man month: 2.5mV / 47kohm
MC: 170 microvolts/220 ohms
tuner, compact disk, aux, tape:150mV /, 22kohm
|Phono SN ratio
||man month: 88dB (2.5mV input)
||Bass: ±10dB (50Hz)
Treble: ±10dB (20kHz)
|Loudness control (VR-30dB)
||Width 478x height 158.4x depth of 397mm