Audio Database


DC power amplifier with a diamond differential circuit.

A diamond differential circuit is used in the pre-drive stage.
The first stage employs a direct-coupled voltage-differential amplifier circuit with current source using dual FET with low noise and large current flow, the second pre-drive stage employs a dual complimentary service diamond differential circuit with cascode and bootstrap, and the final power stage employs a current-differential push-pull circuit using Sansui Custom NM transistors.
Coupled with a 2-pole phase correction circuit, it realizes low-distortion transmission up to high frequencies.

The power supply section has a large EI transformer located in the center of the chassis.
This transformer has two independent windings on the left and right sides and two rectifier circuits to maintain reliable operation even at full power.
It also uses a newly developed custom electrolytic capacitor 15,000 μ Fx4.

In order to dissipate heat generated by the power transistor, a large chimney type heat sink and a bonnet design that utilizes the heat sink are used to cope with heat radiation.

It is equipped with a large power meter.
The peak indicator is a meter scale (PAT. PEND) that embeds a peak meter between 0 dB and + 5 dB. When a peak level is detected, the indicator lights up and quickly indicates the peak value of a pulse signal or music source.

Symmetric monophonic construction is used to make the most of the diamond differential circuit.
Blocks are arranged according to the signal flow.
In addition, the wiring from the output transistor to the output terminal in the amplifier is shortened by the left and right independent Out Put changeover switches, and transmission loss is minimized.

Left and right channel independent input volume.

Power switch with large indicator.

Two spare AC outlets (interlock 100W, non-interlock 200W).

Large earth terminal.

EIA standard rack-mount adapter included.

Model Rating
Type Stereo DC power amplifier
Effective output (both channel operation) 110W + 110W (8 ohm, 10 hz to 20 khz, THD 0.008%)
110W + 110W (8 ohm, 1 khz, 0.003% THD)
Total harmonic distortion rate (10 Hz to 20 kHz) 0.008% or Less (8 Ω)
Intermodulation distortion factor (70 hz : 7 khz = 4 : 1) 0.008% or Less (8 Ω)
Output Bandwidth (IHF, THD 0.02%, both channel operation) 3 Hz ~ 70 kHz (8 Ω)
Damping factor (IHF, 1 kHz, both channel operation) 100 (8 Ω)
Frequency Response (1W) DC ~ 600 khz + 0 -3dB
Input Sensitivity / Input Impedance (1 kHz) 1V/25k Ω
Signal-to-noise ratio (IHF, A-network, short circuit) 125 dB or more
Channel Separation (IHF) 105 dB or More (1 kHz)
98 dB or More (10 kHz)
Rise time 0.5 μ sec
Slew rate ± 200 V / μ sec
Load impedance 4 ~ 16 Ω
Speaker used A, B : 4 ~ 16 Ω
A + B : 8 Ω or more
Rated power consumption (Electrical Appliance and Material Control Law) 250W
External dimensions Width 430x Height 187x Depth 430 mm
With Rack-Mount Adapter : Width 482x Depth 450 mm
Weight 20kg
With Rack-mount Adapter : 20.3 kg