SANSUI AU - α 707L Extra

Commentary

A pre-main amplifier based on AU - α 707 Extra and adopting LAPT which is an audio-only transistor.

Linear Amplification Power Transistor (LAPT), newly developed for audio only, is used to improve linearity at low levels.
In the LAPT, pure copper material is used, and the generation of magnetic strain is eliminated by making it completely nonmagnetic up to the bonding wire, and the cut-off frequency is improved to 50-60 MHz by improving the internal structure of the element, which is three times higher than conventional products.

A -X balanced circuit is used for the circuit structure, and a NEW diamond differential circuit with cascade connection of first stage FETs provides excellent high-frequency characteristics.

The power supply section is placed in the center and the power amplifier section mounted on a large heat sinker is arranged symmetrically in a twin monaural construction. This eliminates interference from vibration sources that adversely affect sound quality, and achieves excellent sound localization.

It is equipped with a balance input, and by connecting a CD player equipped with a balance output, balance transmission and amplification from the source to the speaker is possible.

A balanced power supply is adopted for the power supply part, and various adverse effects are suppressed by making it a closed loop which is independent from ground.
In addition to large transformers, custom-made electric field capacitors and high-speed rectifier elements are used to reduce impedance.

We use newly developed quality parts that are carefully examined one by one, mainly for power supplies and parts that directly pass music signals such as capacitors, resistors, semiconductors, and coils.

Equipped with functions such as Power Amp Direct, Source Direct and Rec Selector.

The volume is equipped with 6 continuous detent volume.

Model Rating

Type	Integrated amplifier
Power Amplifier Unit
Effective output (10 Hz to 20 kHz Both channel drive)	160W + 160W (6 Ω) 130W + 130W (8 Ω)
Dynamic Power	405W (2 Ω) 320W (4 Ω) 210W (6 Ω)
Total harmonic distortion factor (at effective output)	0.003% or Less (8 Ω)
Cross modulation distortion factor	0.003% or Less (8 Ω)
Damping factor	150 (8 Ω)
Frequency Response (1W)	DC ~ 300 khz + 0 -3dB
Input Sensitivity / Impedance	1V/5k Ω (1 kHz)
Signal-to-noise ratio (A network)	120 dB or more
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 characteristic	Phono MM : 20 Hz to 20 kHz ± 0.2 dB CD, Tuner, Line, Tape/DAT1, 2, 3 : DC ~ 200 khz + 0 -3dB
Signal-to-noise ratio	Phono MM : 88 dB or more Phono MC : 70 dB or more CD, Tuner, Line, Tape/DAT1, 2, 3 : 110 dB or more
Tone control	Bass : ± 6 dB (50 Hz) Treble : ± 6 dB (15 kHz)
Subsonic filter	16 Hz (-3dB), 6dB/oct.
Loudness	+ 4 dB (50 Hz), + 3 dB (10 kHz)
<General>
Rated power consumption	330W
External dimensions	Width 466x Height 163x Depth 450 mm
Weight	22.0kg