LUXMAN C-08

Commentary

A control amplifier developed with the aim of becoming a power amplifier driver that can obtain sufficient signal level required by the power amplifier and drive reliably.

CSSC (complimentary service Single Stagger Circuit) circuit is adopted to improve basic circuit characteristics while minimizing excessive control.
The CSSC circuit is a single-stage amplifier circuit of pure complimentary service directly connected to all stages. In order to remove the filter effect on the sound quality of the voltage amplification stage, the multi-stage voltage amplification is not used. Moreover, the transparency of the filter is improved by increasing the bare characteristics, and the natural reproduction sound is obtained.
The first stage is a complimentary service circuit of FET differential and cascode-connected transistor with clear operation reference point with high impedance. The problem of vertical asymmetry in this configuration is solved by using dual-chip FET and transistor and thermal coupling.
In the driver stage, a Darlington connected complimentary service emitter-follower circuit with improved current gain and reduced output impedance is used to enhance the power amplifier driver function.

OD β (optimized Dual NFB) B) circuit which makes full use of original NF technology.
Because the circuit configuration is fully developed with bare characteristics of the circuit, 100% DC feedback is possible, and the circuit configuration that eliminates the DC servo amplifier that was unnecessary for sound quality is realized.

The power supply section uses a power transformer with a double shield consisting of a copper core and an exterior case.
Two independent secondary windings are used for the flat amplifier and the accessory circuit. For the flat amplifier, L/R individual regulators are installed after rectification to eliminate mutual interference through the power supply.
In addition, the circuit and dedicated regulator are placed on a single board to minimize the power supply line.
In addition, a high-inertia power source is adopted to further improve the musical performance.
This is designed to increase the instantaneous supply capability and capacity of the power supply part, which is the basic performance of the power supply circuit, minimize NFB, and when the fluctuation is small due to time delay control, reduce the control to make the fluctuation more gradual. This enables natural supply with small fluctuation range even on a short time axis.

Eight input terminals are installed, and in order to give priority to sound quality, relay switching by nitrogen gas sealed charge contact is adopted.
In addition, by separating the ground side as well as the hot side, the noise around through the ground loop is taken into consideration.

It uses a unique 32-point fixed resistance switching rotary switch type ultimate attenuator.
Non-magnetic resistors corresponding to the attenuation at each point are mounted one by one on a glass epoxy substrate with a gold plating pattern. In addition, a shield structure made of extruded aluminum die-cast material is applied to ensure high sound quality.

In the chassis structure, each stage is separated by a shield plate, and a 9-box structure with increased rigidity of the case is adopted, which effectively blocks leakage flux and high-frequency noise.
In addition, noise inside and outside the chassis has been greatly reduced and eliminated by adopting a mechanical floating mounting system in which the transformer is floated from the main chassis, by installing shield wires on the entire surface, and by introducing anti-noise parts.
In addition, a 5-point grounding FRP bottom chassis with high rigidity and high mass is adopted.

Special attention is put into each part, and custom parts such as non-magnetic resistance, electrolytic capacitor, copper styrene capacitor, cohabiting bus bar, high purity 6N copper cable are used.
In addition, a newly designed output transformer with a permalloy core and strict electrostatic and electromagnetic shielding is adopted.

Uses unique seesaw tone control.
By varying the feedback resistance in the NF loop, a linear slope is given to the frequency characteristics in a seesaw manner. Instead of separately performing low and high band peaks and attenuation, the balance of energy around 1 kHz is corrected gradually as a whole, enabling practical sound quality correction with excellent phase characteristics.

Equipped with left and right independent balance attenuators.
In consideration of sound quality, a fixed resistance switching type with non-magnetic resistance is adopted instead of sliding variable resistor.
Relay is used for on / off, and L/R can be adjusted in 3 steps of + 1 dB, + 2 dB and + 3 dB in 1 dB steps.

Equipped with line phase sensor, polarity management of power supply circuit is possible.

Model Rating

Type	Control amplifier
Input Sensitivity / Impedance	CD, Line1, 2, 3, 4, 5, Tape1, 2 : 150mV/40k Ω
Output level	Output1 Coaxial : Rated 1 v / Maximum 10 v Output2Balance : Rated 1 v / Maximum 10 v
Total harmonic distortion factor	0.005% or Less (at Rated Output)
Frequency characteristic	8 Hz to 100 kHz ± 0.5 dB or less
Signal-to-noise ratio	110 dB or more (IHF-A)
Accessory function	Tape dubbing : 2 systems (1 → 2, 2 → 1) REC OFF Tone control Line phase sensor
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	23W
Maximum external dimensions	Width 465x Height 186x Depth 467 mm
Weight	25kg(NET)