Audio Database


A preamplifier with separate control unit and power supply unit.

The attenuator section uses a balanced type rheostat mode attenuator with excellent SN ratio in actual operation and no difference in characteristics between hot and cold sides in balanced transmission.
Since the volume is adjusted between hot and cold, there is no variation between hot and cold, and the noise level is linearly reduced as the volume is reduced, which provides better conditions than the catalog specifications at normal listening levels.
In addition, there is only one contact point with the resistor, and there is less noise degradation factor than conventional two points, making it possible to transmit high-purity signals.

The input circuit is equipped with a NEW inverted Σ balance circuit so that both balanced and unbalanced inputs can be made under the same conditions.
In addition, it has a unique simple balanced direct design that does not require a conversion transformer or amplifier, enabling high-quality signal transmission. The high CMRR the high CMRR balanced amplifier improves the transmission error between hot and cold by the function of the compensation amplifier.
In addition, both the hot and cold outputs can be used as unbalanced outputs for GND. Thus, both balanced and unbalanced outputs have the same quality.

In order to reduce the influence of noise from the AC power supply, the power supply and signal amplifier are configured as separate units, and a pure power generator is installed in the power supply unit.
The pure power generator is equipped with a low-distortion, high-stability sine wave transmitter. The sine wave output is amplified by a BTL configuration UHC MOS single push-pull power amplifier and used as a Iori. The output is used as a power source to protect music signals from harmonic noise and amplitude fluctuation mixed in the power source.
In addition, the built-in oscillator supply frequency to be set to 100 Hz, 150 Hz, 200 Hz, 250 Hz, or 300 Hz. This realizes an excellent current supply capability, and the sound field can be controlled by selecting the frequency.

The chassis is made of S1 series unique non-magnetic sand castings with excellent vibration resistance and high precision processing without magnetic influence.

Model Rating
Type Preamplifier
Control Unit
Rated output Normal, Inverted : 1 V
Input Sensitivity / Impedance Phono MM : 2.5mV/47k Ω
CD, Tuner, Tape1, 2 : 150mV/47k Ω
Balanced1, 2 : 150mV/100k Ω
RIAA deviation Phono : 20 Hz to 20 kHz ± 0.3 dB
Total harmonic distortion factor Not more than 0.005%
Signal-to-noise ratio (A network) Phono MM : 91 dB (input terminal short-circuit, input signal 5 mV)
CD, Tuner, Tape1, 2 : 108 dB (input terminal short circuit)
External dimensions Width 434x Height 145x Depth 426 mm
Weight 17.4kg
Power Supply Unit
Power supply voltage 100 VAC, 50Hz/60Hz
Power consumption 110W
External dimensions Width 434x Height 145x Depth 426 mm
Weight 24.8kg
Remarks AC Cord Length : 2m
DC Cord Length : 1m