|SANSUI AU-alpha 777DG
|96,500yen(around the 1989 time)
The Integrated Amplifier which carries the digital
analog converter of a MASH scheme.
New L.D.C.S (linear & direct D/A
combartion system) by a MASH scheme is carried in the D?A converter part.
MASH scheme is a D-A-conversion scheme made into the criteria of a translation
of the frequency by a crystal oscillator,By high order oversampling and the 3rd
noise shaping, a digital signal is changed into an analog signal highly precise
in an instant, and the occurrence of zero cross distortion or non-linear
distortion has the special feature of not occurring theoretically.
AU-alpha 777DG, in order to employ the high precision of a MASH scheme
efficiently, the precision near a crystal oscillator is offered, and also a lock
range adopts a large LT element, and it is considered as the original linear
& direct D/A combartion system (L. D.C.S).
In New L.D.C.S, total upgrade
is aimed at from the off-site circuitry, and the SN ratio is improved further.
In the power-source part, the transformer for exclusive use is carried
in each of a digital circuit and an analog circuit, and the separation put into
practice from the power-source part is performed.
This has prevented mixing
to analog parts, such as an electromagnetic-wave pulse peculiar to digital one.
The alpha-X balance circuit which poured the original know-how into the amplifier part is adopted, and the circuitry itself has canceled a noise and
distortion by balance operation.
The power-source part was placed in the
center and the twin monophonic construction which arranges a power unit
symmetrically is adopted. Since a digital circuit part is shielded and arranged
on the outside of the left channel unit and also an analog input part is
shielded and arranged by this on the outside of the right channel unit, the
digital part and the analog part are separated clearly.
Since it is
compatible in a tone quality and convenience, the remote controller which
adopted the direct-access rotary switch is attached, and the volume up and down
by a 6-unit volume and a source changeover are possible.
Functionalities, such as Source-Direct operation, an REC serector, and a
direct-access rotary switch, are carried.
The gilding input terminal,
the polar attached-indicator very-thick power cord, and the AC outlet are adopted.
There was sub- wood as an option.
||Alpha-X balanced integrated amplifier
||108dB or more (EIAJ)
||0.003% or less
|Digital input level
|An optical input
||660nm (light-generation wavelength)
|<Power amplifier part>
|Effective output (10Hz - 20kHz)
Both channel operation
|THD (at the time of an effective output)
||0.003% or less (8ohms)
|Cross modulation distortion
||0.003% or less (8ohms)
|Frequency characteristic (1W)
|TIM distortion (SAWTOOTH)
||Below a limit-of-measurement value
|Phono man month: 2.5mV / 47kohm
MC: 300 microvolts/100 ohms
compact disk, Tuner, Line, Tape/DAT1, 2 or
3:150mV / 20kohm
|Phono maximum permissible input
||Phono man month: 20Hz-20kHz}0.2dB
compact disk, Tuner, Line, Tape/DAT1, 2, and 3:DC-200kHz+0 -3 dB
|SN ratio (A network)
||Phono man month: 88dB or more
70dB or more
compact disk, Tuner, Line, Tape/DAT1, 2 or 3:110dB or more
||Bass: }6dB (50Hz)
Treble: }6dB (15kHz)
||16Hz (-3dB), 6dB / oct
||+ 6dB (50Hz), +4dB (10kHz)
||Width 430x height 163x depth of 450mm
||Wireless remote control RS-1130
||Real sub- wood SW-AU1 (10,000yen)