|SANSUI AU-alpha 707MR
The Integrated Amplifier of memory-read series which
carries a New Hyper alpha-X balance circuitry.
In order to make into
operation top zero an occurrence of the electrical noise generated inside a
circuitry, the New Hyper alpha-X balance circuitry is adopted.
By CMRR, this
circuitry developed further into the Hyper alpha-X balance circuitry the Wilson
current mirror quantity CMRR type constant current circuit which realizes the
with a theoretical value of 140dB modification effect, and was developed in
it,It has the composition of having carried the up-and-down symmetrical balance
type constant current circuit of the Advanced Wilson current mirror scheme.
It has succeeded in making the driver stage into the closed loop by another
coil, and the asymmetry of the element which happens in a circuitry preparing
the variation in the electric current by DC offset of a cause by this, and also
raising the stability of an operation of the circuitry itself.
main power-source part of an output stage which concentrated the transformer,
the electrolytic capacitor, etc. is also made into the closed loop by another
coil, lets all the systems pass from the entry point of sound to an outlet, and
is building the optimal operating environment for balance amplifier.
Furthermore, power device NM-LAPT only for an audio is adopted.
Since the New diamond differential circuit is adopted as the drive stage
in order to improve the responsibility to a momentary signal, and - output can
be taken out without phase inversion, the current-supply-source capacity over
the input signal which changes violently is high, and the outstanding property
has been realized.
Furthermore, in addition to the cascade connection of FET
of the first rank, the circuitry is made into a wide range and the thing which
had high-speed-ized and was more excellent in the performance characteristic of
New alpha-X balance amplifier by using a driver power-source part as an
up-and-down symmetry and a balanced type.
Moreover, the effect of preventing
a tone-quality failure also in the case of the interconnection with the external
equipment which differs in an impedance is demonstrated.
The New alpha-X
balance power source is adopted as a power-source part.
The output stage was
made the balanced type closing, the driver stage was made into the up-and-down
symmetrical balance type constant-current regulated power supply, and the ill
effect to the tone quality of the imbalanced electric current of the power
source leading to a tone-quality failure is prevented by having the closed-loop
stream composition which carried out full independence from the grounding.
Furthermore, a large-sized power transformer, an ellipse form electrolytic
capacitor, and first recovery diode are adopted.
In order to prevent an
oscillation of a power supply system and a signal system, the strengthening twin
monophonic construction is adopted.
Power-source parts which are the sources
of an oscillation of a power supply system, such as a large-sized transformer
and an electrolytic capacitor, were installed in the central part, and from the
power substrate, power units which are the sources of an oscillation of a signal
system, such as a power transistor and a radiator, were considered as the
right-and-left independency, and are arranged symmetrically with case both
sub-s. While this prevents an interference on either side, the optimal weight
balance is secured and the natural oscillation of amplifier is controlled
In order to intercept the channels of communication of an
oscillation, the isorated mechanical feedback developed by the original know-how
Between a master volume, between chassis and a power transistor, and a radiator, the internal loss used the isolation part with the greatly
excellent vibrational absorption effect made from a pure copper for the attachment base of an electrolytic capacitor etc., and has controlled the
oscillation at it.
Furthermore, between an insulator and a sole plate, the
isolated rate of the Teflon tapes and Teflon sheet whose molecular structure is
stable was used abundantly and carried out between the radiator, the bonnet, and
the chassis etc., and it is coped with to the tone-quality failure by
The high-quality sound part of the ellipse insulator
metallurgy plating bar of a special structure is adopted.
amplifier direct input corresponding to three direct inputs is carried, and it
can link with a power amplifier part directly.
The source power direct
which transmits the input signal of all the usual lines to a power amplifier
part without letting an accessories circuitry pass is carried.
6-unit Detent volume is adopted as a volume.
|<Power amplifier part>
|Effective output (10Hz - 20kHz)
Both channel simultaneous operation
|THD (at the time of an effective output)
||0.003% or less (8ohm)
|Cross modulation distortion
||0.003% or less (8ohm)
|Frequency characteristic (1W)
||1V / 5kohm (1kHz)
|SN ratio (A network)
||120dB or more
|TIM distortion (Sawtooth)
||Below a limit-of-measurement value
|Phono man month: 2.5mV / 47kohm
Phono MC: 300 microvolts/100 ohm
compact disk, Tuner, Line, Tape/DAT1, 2:150mV /
|Phono maximum permissible input
|the frequency characteristic (1W)
||Phono man month: 20Hz-20kHz}0.2dB
compact disk, Tuner, Line, Tape/DAT1, and 2:DC-200kHz+0 -3 dB
|SN ratio (A network)
||Phono man month: 88dB or more
70dB or more
compact disk, Tuner, Line, Tape/DAT1, 2:110dB or more
||The Bass maximum variation: }6dB (50Hz)
The Treble maximum variation: }6dB (15kHz)
||16Hz (-3dB), 6dB / oct
||+ 6dB (50Hz), +4dB (10kHz)
||Width 471x height 162x depth of 452mm