Audio Database

AU - α 507 xr

A pre-main amplifier developed by inheriting the design technology of high-grade machines.

It uses a DC amplifier configuration that directly amplifies from DC to high end.
Since the DC amplifier does not require a capacitor in the signal path, the sound quality is not affected by the capacitor and the time constant in the low frequency range can be reduced.

The power supply section uses a heavy-duty power transformer with high-density filler for enhanced vibration and heat resistance, and an audio electrolytic capacitor with excellent charging and discharging speed.
In addition, the power transformer is installed by a strap mount method in which it is hung upside down from the upper part of the body, and the transmission of vibration is prevented by using the self-weight of the transformer.

Equipped with 4-mode Presence Control to adjust sound quality balance according to listening conditions.
Loudness 1 and 2 raise both the high and low frequencies simultaneously, and bass boost 1 and 2 raise only the low frequencies that are often lacking in small speakers.

The sound quality parts such as resistance are carefully selected. In addition, each part is made non-magnetic and vibration proof performance is thorough, and the basic circuit is also improved to acquire sound quality suitable for the name of XR.

In order to realize purer music playback, we have adopted Source Direct, which minimizes the signal transmission path.
Accessories such as tone control, balance volume and subsonic filter are omitted to enable pure transmission.

Equipped with an MC/MM phono equalizer.

Mini-detent volume is used for volume.

Model Rating
Type Integrated amplifier
Effective output (20 Hz to 20 kHz, both channel operation) 80W + 80W (6 Ω)
60W + 60W (8 Ω)
Total harmonic distortion factor (at effective output) 0.008% or Less (8 Ω)
Cross modulation distortion factor 0.008% or Less (8 Ω)
Damping factor 135 (8 Ω)
Input Sensitivity / Input Impedance (1 kHz) Phono MC : 300 μ V/100 Ω
Phono MM : 2.5mV/47k Ω
CD, Tuner, Line, Tape1, 2 : 150mV/47k Ω
Frequency characteristic Phono MM : 20 Hz to 20 kHz ± 0.5 dB
CD, Tuner, Line, Tape1, 2 : DC ~ 200 khz + 0 -3dB
Signal-to-noise ratio Phono MC : 70 dB or more
Phono MM : 88 dB or more
CD, Tuner, Line, Tape1, 2 : 110 dB or more
Tone control Maximum variation of Bass : ± 8 dB (50 Hz)
Maximum variation of Treble : ± 8 dB at 10 kHz
Subsonic filter 16 Hz (-3dB), 6dB/oct.
Loudness 1 + 9 dB at 50 Hz, + 3 dB at 10 kHz
Loudness 2 + 9 dB at 50 Hz, + 6 dB at 10 kHz
Bus Boost 1 +10dB(50Hz)
Bus Boost 2 +11dB(50Hz)
Rated power consumption 160W
External dimensions Width 430x Height 135x Depth 365 mm
Weight 10.5kg