Audio Database

SU-8080
Commentary

A pre-main amplifier that employs an integrated DC configuration to achieve more faithful waveform transmission.

The DC main amplifier section, which directly drives the high-level input, consists of a first stage differential amplifier, a voltage amplifier stage with a pure resistance load, an output stage with an emitter follower and a two stage Darlington connection, and the gain is increased to 42 dB to directly drive the high-level input.

By making the power supply circuit configuration independent on the left and right, transient distortion is reduced.
In addition, the power supply of the voltage amplification stage is all constant voltage, and not only crosstalk distortion but also self-transient distortion in the own channel is minimized.

The transformer has a strict magnetic shield and is located on the diagonal most distant from the equalizer circuit. This is a low-noise design.

The PhonoSN ratio has been improved by adopting the newly developed low-noise transistor M47L for the first stage amplifier.
In addition, excellent characteristics have been obtained by the adoption of a high-precision equalizer element.

For tone control, we use a volume where the CR is out of the signal system at the midpoint.

Equipped with equalizer subsonic filter.

Cartridge load can be switched to 4 types independent of resistance capacitance.

Model Rating
Type Integrated DC amplifier
Main Amplifier Section
Effective output (simultaneous driving of both channels) 72W + 72W (8 Ω, 20 Hz to 20 kHz)
75W + 75W (8 ohm, 1 khz)
Total Harmonic Distortion Factor (1 kHz, 8 Ω) 0.02% (at rated output)
0.0015% (at rated output -3dB, 36W output)
Output Bandwidth (Both channel drive, 8 Ω) 5 Hz to 40 kHz
Frequency characteristic 20 Hz ~ 20 kHz + 0 -0.1 dB
DC ~ 100 kHz + 0 -3dB
Signal-to-noise ratio (IHF-A) 115dB
Residual noise 100 μ V
Damping factor 70 (8 Ω)
Input Sensitivity / Impedance 1V/50k Ω
Load impedance Main or Remote : 4 Ω ~ 16 Ω
Main + Remote : 8 Ω ~ 16 Ω
Preamplifier Section
Input Sensitivity / Impedance Phono1, 2 : 2.5mV/27k Ω, 47k Ω / low, high
Tuner, Aux, Tape deck1, 2 : 200mV/35k Ω
Total harmonic distortion factor 0.01%
SN ratio (IHF-A, main input : direct/via tone) Phono1, 2 : 88dB/88dB
Tuner, Aux : 106dB/100dB
Frequency characteristic Phono1 and 2 : RIAA standard curve ± 0.2 dB
Tuner, Aux : 20 Hz to 20 kHz + 0 -0.1 dB
Phono maximum allowable input (1 kHz, RMS) 280mV
Rated Output / Impedance Pre-out : 1V/1k Ω (Rating), 9V/1k Ω (Maximum)
Rec out1, 2 : 200 mV
Tone control Bass : ± 7.5 dB (50 Hz)
Treble : ± 7.5 dB (20 kHz)
Filter EQ Subsonic : 30 Hz, -12dB/oct.
High : 10 kHz, -6dB/oct.
Muting -14dB
Loudness control (Volume -30dB) +8dB(100Hz)
<General>
Pwer 100 VAC, 50Hz/60Hz
Power consumption 172W
External dimensions Width 450x Height 140x Depth 371 mm
Weight 13.5kg