Audio Database

SU-3500
Commentary

A pre-main amplifier that improves circuit stability with a constant voltage power supply of ± 40 v.

The EQ circuit is a 3-stage direct-coupled circuit configuration using a differential-amplified 2-power supply system with a pure complimentary service SEPP output stage.
In addition, the input impedance can be switched in 3 levels of 25k Ω / 50k Ω / 100k Ω.

The main amplifier section is composed of a pure complimentary service OCL circuit connected to all stages. In addition, the power supply voltage is lowered and two 10,000 μ F electrolytic capacitors are used for the output stage to pursue low distortion rate and high stability.

The tone control circuit is NF-type and equipped with a tone defeat switch that instantly restores the characteristics.

Uses a preset volume that can also be used as an audio mute.

Two tape decks can be connected.

Equipped with two Phono terminals.

Model Rating
Type Stereo pre-main amplifier
Circuit system Fully complimentary service all-stage direct-coupled differential-amplification OCL circuit
Music power 190W (4 Ω)
125W (8 Ω)
Effective power
(1 kHz, both channel drive)
55W + 55W (4 Ω)
43W + 43W (8 Ω)
Output Bandwidth (8 ω) 5 hz to 70 khz -3dB
Harmonic distortion factor 0.08%
Signal-to-noise ratio Phono:70dB
Damping factor 100 (8 Ω)
Phono maximum allowable input 510mV(1kHz)
Tone control Bass : ± 12 dB (50 Hz)
Treble : ± 12 dB (20 kHz)
Low filter 30 Hz, -12dB/oct.
High filter 8 kHz, -12dB/oct.
Pwer 100 VAC, 50Hz/60Hz
Power consumption 110W
External dimensions Width 410x Height 140x Depth 340 mm
Weight 10.2kg