Audio Database

AU - α 505 rx

A pre-main amplifier with newly developed audio elements mounted on the output stage.

In the conventional case, the temperature detection and correction circuit is connected externally to the power transistor. This causes a loss in time for heat transfer, causing the operating point to fluctuate. This causes a difference in the amplification factor with respect to the music signal, causing distortion especially at small signals.
However, the output stage is equipped with a newly developed SAP (transistor with temperature compensation function) audio element with built-in temperature detection and compensation circuits, and temperature compensation is performed almost in real time. As a result, the operating point dynamically follows the strength of the music signal.
Since the distortion factor does not vary depending on the output, the bare characteristics at low to medium volume are stabilized.

The well-balanced layout of the transmission and amplification circuits reduces various adverse effects on sound quality, such as signal jumping in the circuits.

In order to realize purer music playback, we adopted Source Direct, which minimizes the signal transmission path.

It is equipped with 37 key unified remote control as standard for improved operability.

Model Rating
Type Pre-main amplifier
Effective power 80W + 80W (both channel operation, 20 Hz to 20 kHz, 8 Ω)
Total harmonic distortion factor 0.04% or Less (20 Hz to 20 kHz, 8 Ω at Rated Output)
Input Sensitivity / Input Impedance
Phono (MM) : 3.3mV/47k Ω
CD, tuner, line, Tape1, 2 : 200mV/47k Ω
Maximum allowable input Phono (MM) : 100 mV (1 kHz, THD : 0.1%)
Frequency characteristic Phono (MM) : 20 Hz to 20 kHz ± 0.5 dB
CD, Tuner, Line, Tape1, 2 : 10 Hz ~ 70k + 0 db, -3dB
Signal-to-noise ratio (A network
Short circuit)
Phono (MM) : 75 dB or more
CD, Tuner, Line, Tape1, 2 : 102 dB or more
Tone control Maximum variation of Bass : ± 8 dB (50 Hz)
Maximum variation of Treble : ± 8 dB at 10 kHz
Loudness (Volume -30dB) +9dB(50Hz)
Rated power consumption 190W
Non-signal power consumption 22W
Standby power consumption 12W
External dimensions Width 430x Height 143x Depth 351 mm
Weight 10.2kg