SANSUI AU - α 707 dr

Commentary

This is a pre-main amplifier that inherits the concept of SANSUI's amplifier manufacturing to the details.

A 4-amp push-pull advanced alpha-X balance circuit with amplifiers on the + and - sides of the output drives the speakers from both + and - sides.
By completely separating the amplifier circuit and ground circuit, it is free from external noise and in-phase distortion. In addition, by adopting NM-LAPT for audio only, the impedance of the circuit is reduced and dynamic frequency characteristics are improved.

The power supply section has a closed-loop configuration, newly developed electrolytic capacitor and power transformer, and the fast recovery diode is custom-made to ensure a high-speed and stable power supply.

In order to effectively suppress the vibration of the power supply system and signal system, a reinforced twin monaural construction is adopted to realize the optimum weight balance.
In addition, the vibration transmission path between the master volume and the chassis is completely cut off by the integrated mechanical feedback which effectively utilizes the isolation parts made of pure copper.

We pursue the quality of each part focusing on the part where music signals directly pass through. We are also particular about ensuring high sound quality with the vibration dispersion and non-resonance design of the insulator and the specification of bronze screws for other parts.

Equipped with a power amplifier / direct input that directly inputs the audio signal of the digital source to the power amplifier section, high purity transmission and amplification are possible.
In addition, since it is equipped with a balance input, if it is connected to an external device capable of balance output, a playback system by balance transmission and input can be constructed.

The Source Power Direct allows all normal line inputs to be connected directly to the power amplifier, allowing the pure sound of the source to be reproduced without passing through the less frequently used accessory circuit.

It features a 6-channel detent volume, a gold-plated input terminal, a large speaker terminal, real sidewood, and a polarity display power cord / AC outlet.

Model Rating

Type	Integrated amplifier
Power Amplifier Unit
Effective output (10 Hz to 20 kHz Simultaneous operation on both channels)	6 Ω : 160W + 160W 8 Ω : 130W + 130W
Total harmonic distortion factor (at effective output)	0.003% or Less (8 Ω)
Frequency Response (1W)	DC ~ 300 kHz, + 0 -3dB
Cross modulation distortion factor	0.003% or Less (8 Ω)
Damping factor	150 (8 Ω)
Input Sensitivity / Impedance	1V/5k Ω (1 kHz)
Signal-to-noise ratio (A network)	120 dB or more
Dynamic Power	2 Ω : 405W 4 Ω : 320W 6 Ω : 210W
TIM (SAWTOOTH)	Measurement limit value or less
Slew rate	200 V / μ sec
Rise time	0.5 μ sec
<Pre-part>
Input Sensitivity / Impedance (1kHz)	Phono MM : 2.5mV/47k Ω Phono MC : 300 μ V/100 Ω CD, Tuner, Line, Tape/DAT1 / 2 / 3 : 150mV/20k Ω
Phono maximum allowable input	MM(THD 0.01%):210mV MC(THD 0.1%):21mV
Frequency Response (1W)	Phono MM : 20 Hz to 20000 Hz, ± 0.2 dB CD, Tuner, Line, Tape/DAT-1 / 2 / 3 : DC ~ 200 khz, + 0 -3dB
Signal-to-noise ratio (A network)	Phono MM : 88 dB or more Phono MC : 70 dB or more CD, Tuner, Line, Tape/DAT-1 / 2 / 3 : 110 dB or more
Tone control	Maximum variation of BASS : + / - 6 dB at 50 Hz Maximum change of TREBLE : ± 6 dB (15 kHz)
Subsonic filter	16 Hz (-3dB), 6dB/oct.
Loudness	50Hz:+4dB 10kHz:+3dB
<General>
Rated power consumption	330W
External dimensions	Width 460x Height 159x Depth 446 mm
Weight	22.5kg