|SANSUI AU-alpha 907DR
The Integrated Amplifier which polished up a
circuitry, an organization, and three factors of a part carefully, and was
completed by making it join together.
NM-LAPT (Non Magnetic Liner
Amplification Power Transistor) developed as a power transistor only for an
audio is adopted as the power stage.
NM-LAPT is what put into practice and
carried out pure-copper material until it resulted in the bonding wire, and it
had, carried out the workshop of the destructive resistance (PC) to cut-off
frequency (fT), and has realized the outstanding RF property and big
electric-current threshold value.
Since the grounding circuitry of a
power circuit and the grounding circuitry (negative of an output) of the amplifying circuit were connected, the reverse current from the speaker side
flowed into the amplifying circuit, and in order to prevent that deterioration
of a tone quality occurs, the Advanced alpha-X balance circuitry original with
an SANSUI is introduced.
The circuitry itself is intercepting an exogenous
noise and inphase distortion by having the transmit and the balance stream
composition to which an amplification is carried out simultaneously which the amplifying circuit became independent of completely from the grounding
Moreover, the impedance of a circuitry is lowered and the dynamic
frequency characteristic is raised by inhibiting the influence on a passage
signal as much as possible.
Furthermore, by + and - side having 4 amplifier
stream compositions which had exclusive amplifier, respectively, a forcible
sound is gained by the low distortion for the push pull scheme which + and -
side drives from bothways on the same requirements.
The completeness of
the diamond operation circuitry which can also take out - output without phase
inversion is raised further.
By making FET of the first rank into cascade
connection, a wide range and high speed-ization were attained and the
outstanding broader-based property is acquired. Moreover, the influence produced
by the difference in an impedance with an external equipment is reduced sharply.
The power transformer (IDEAL SILENT POWER TRANSFORMER) and the capacitor
for power sources were developed newly, and it has succeeded in the large
improvement in power-feeding capacity and its stability.
In the transformer,
the primary sub- adopts OFC lead wire as a drawer lead, and is also suppressing
magnetic induction (リケージ flux) on the minimum level. This has called it the
transformer weight of 13kg by enclosure of a high-density fill, study of the
insulating material, etc. while making a shielding the quadruplicate of a copper
short ring, a double silicon steel plate, and also a stops case.
electrolytic capacitor and first recovery diode were also changed completely, and have adopted the thing only for the highest tone quality.
of the power source etc. has stopped to the minimum various ill effects which it
has on a music signal with the closed-loop stream composition which became
independent of the NEW alpha-X balance power source in which all are clean at a
custom-made low-impedance, and a grounding.
The strengthening twin
monophonic construction which placed the power-source part in the center and has
arranged the power unit symmetrically was introduced, each part article which
raised the intensity prevented deterioration of the tone quality by oscillation, and the outstanding image orientation and phase response are gained.
large-sized insulator and pure-copper bases, a copper plating part, etc. of a
pure-copper Naked which stuck not only a control of the oscillation by a twin
monophonic construction but the felt place have a large internal loss to each
part, and are using the high thing of the vibrational absorption effect for it
moreover, the pure-copper material isolation which was being used
from the former between the transformer, between chassis and an electrolytic
capacitor, between chassis and an amplifier stand, and the sole plate etc. --
between a master volume, between chassis and a radiator, and power substrates --
andIt is newly adopted as a transformer, an electrolytic capacitor, a power
substrate, and the power-source substrate itself.
Also in the installment
structure of each part, attaching the case of a transformer to a chassis for
example, rather than attaching the main unit of a transformer to a chassis
directly etc. has succeeded in intercepting the propagation root of an
oscillation effectively by isorated mechanical feedback.
improvement in a tone quality, the quality of each part is also pursued
Not only a development of a transformer and a capacitor but
adoption of the rolling copper substrate to a power platform or a power-source
substrate, the copper plating to a rear panel, a coating of the bonnet by the
coating with which a part for copper was mixed, adoption of the screw made from
bronze, etc. are performed.
Thorough investigation of
non-magnetic-material-izing, the measure against vibration proof,
low-impedance-izing, and the high-speed-izing is carried out for each part.
By carrying out the direct input of the audio signal to a power
amplifier part, the input termination which realizes a high purity transmit and
amplification of the digital source is equipped.
Since there is also a
balance input in addition to a normal input, a setting according to a balance
transmit and an amplification by the interconnection with the external equipment
equipped with the balance output is possible.
The source power direct
switchpoint which transmits all the line-input signals to power amplifier as
they are by one-touch is carried.
Without letting any accessories
functionalities pass, it connects and amplifies direct and a pure sound of the
source is reproduced.
At the time of an interconnection of the compact
disk player to a power amplifier direct, the recording functionality in which an
effective sound recording and listening can be performed is equipped.
example, it is possible to back-record compact disk linked to Normal 2 and other
sources etc., hearing the source inputted into Normal 1.
An all gilding
input terminal, a large-sized speaker terminal, a pure-copper Naked large-sized
insulator, real sub- wood, a polar attached-indicator power cord / AC outlet,
etc. are carried.
|<Power amplifier part>
|Output power (20Hz - 20kHz)
Both channel simultaneous operation, THD0.003%
||0.003% or less (at the time of an Output
power 20Hz - 20kHz, an 8-ohm load intensity)
||DC-300kHz and +0 -3 dB (at the time of 1W
|Cross modulation distortion
||0.003% or less (at the time of an 8-ohm load
||1V / 5kohm (1kHz)
||120dB or more (A network)
|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/DAT1-2-3:150mV
|Phono maximum permissible input
|the frequency characteristic (1W)
||Phono man month: 20Hz - 20kHz, ±0.2dB
compact disk, Tuner, Line, Tape/DAT-1, 2 and 3:DC-300Hz, and +0 -3 dB
|SN ratio (A network)
||Phono man month: 90dB or more
75dB or more
compact disk, Tuner, Line, Tape/DAT-1, 2-3:110dB or more
||The BASS maximum variation: ±5dB (50Hz)
The TREBLE maximum variation: ±5dB (15kHz)
||16Hz (-3dB), 6dB / oct
||Width 460x height 159x depth of 446mm