LUXMAN M-10 -10 Luxman

LUXMAN M-10
¥ 780,000 (released in March 1997)

Commentary

A stereo power amplifier developed in pursuit of the same quality as the B-10/C-10.

The M-10 uses a CSSC circuit, an OD β circuit, and a high inertia power supply in order to enhance the completeness by thoroughly pursuing the basic circuit characteristics before NFB correction.

The output stage has a 4-parallel configuration using 8 Pc200W class multi-emitter transistors per channel. Combined with a strong power supply, the output stage has sufficient drive power even for low-impedance speakers.
It can also be used as a Monaural Power Amplifier with BTL connection.

Equipped with a complimentary service configuration single stagger circuit CSSC (Complementary Single Stagger Circuit) developed by applying high-frequency circuit technology.
In the CSSC circuit, a highly stable common-base type current transmission stage is adopted in the second stage. By greatly improving the phase characteristics, it is possible to operate stably with the minimum level of phase correction, thereby realizing a high-slew rate rise and extremely wide bandwidth characteristics.

The first stage of the circuit configuration uses a low-noise, high-admittance silicon-coupled dual-FET complimentary service input to ensure high impedance reception. By using a cascode bootstrap connection with a dual transistor with good temperature characteristics, high-impedance input is realized up to the high frequency range without degradation.
The second stage adopts a current transmission stage which is also a feature of the CSSC circuit, and a 3-stage complimentary service Darlington circuit is adopted from the drive circuit to the final power stage.

It is equipped with an OD β circuit, a unique NFB technology, in order to balance energy over all bands and ensure uniformity of sound quality.
In general NFB, the direct current and AC regions are separately fed back. The NFB in the AC region affects the sound quality, while the NFB in the DC region affects the sound quality in the low-frequency region, which is close to the DC region. In DC feedback, a DC servo amplifier or other device may be inserted. By introducing a different process only in the DC region, the balance between the DC and AC regions may be different.
In the OD β circuit, to solve this problem from the root, the bare characteristics of the circuit are elaborated to the hardness, and excellent DC stability is ensured only by basic DC feedback without incorporating a DC servo amplifier, etc. In addition, the NFB in the AC region is optimized by LUX's traditional method of NFB, and the energy balance in all bands is maintained.

High-inertia power supply is used for the power supply section.
The NFB in a general constant-voltage power supply circuit has a time lag between feedback and output control for real-time music. When observed on a micro-scale basis, the power supply voltage always fluctuates in small increments. On the other hand, at a point slightly distant from the feedback on the time axis, the fluctuation becomes large and has a significant effect on the music signal.
To solve this problem, the high-inertia power supply is equipped with a large-capacity power transformer to increase the regulation of the AC level, and an original large-capacity custom electrolytic capacitor with excellent instantaneous discharge capability is installed on the output side of the regulator circuit. This structure gives sufficient margin to the power supply and reduces dependence on the regulator.
This structure increases the inertial force of the power supply except for the active circuit, minimizes the NFB of the regulator and control circuit, minimizes the adverse effect on sound quality caused by feedback delay control, and changes small voltage fluctuations into slow fluctuations.

The power transformer uses a 800 VA EI-core transformer that realizes high regulation by thoroughly reducing impedance.
This transformer supplies dynamic energy to music. The secondary winding is composed of three independent windings without interference between circuits.
The primary side of the transformer is shielded from high-frequency noise by wiring material, and the rectifier circuit from the main winding supplied to the output stage uses ultra-high-speed diodes in two parallel circuits per channel to reduce impedance.
The block capacitors use two custom 22,000 μ F power supply capacitors per two channels, for a total of four. These capacitors were developed for audio applications with special specifications for instantaneous discharge capacitors used for strobe light emission, etc. They not only have large capacity but also provide low impedance power supply.

A glass-epoxy board with excellent insulating properties is used for the circuit board, and a 70-micron copper foil is used for the pattern.
In addition, high-purity 6N wire (using two parallel #18 wires) and copper bus bars with thick gold plating are used for important points where a large current flows from the power supply section to the amplifier section and the speakers, regardless of the pattern of the board.

High rigidity box isolation structure is adopted for internal construction.
In this structure, all sections with different roles such as power supply, input, power block and meter control are designed from layout considerations so as not to cause mutual interference. In addition, shielding walls are provided for each block, and electromagnetic noise and high frequency noise are completely eliminated by wrapping electromagnetic absorption tubes around wires that generate high frequency.
In addition, a large mass FRP base of 5-point grounding type with high stability and excellent vibration absorption mode is adopted for the chassis base, and vibration noise generation is suppressed by mounting each part with thick and hard chassis material.

We have developed a large speaker jack that can be connected to a banana plug or a Y-lug jack in addition to a normal speaker cable.
In addition, it is equipped with Spicon terminal which is used in professional sound field.

The input terminal is equipped with 2 systems of XLR/RCA.
These jacks are equipped with 6-stage independent resistance switching attenuators that allow you to select input levels from 6 positions : ∞, 30 dB, -20dB, -12dB, -6dB and 0 while reducing sound quality degradation.

Many custom parts are used and the power transformers, electrolytic capacitors, small capacity capacitors, and copper-styrene capacitors are custom-made from Lux.

AC inlet type is adopted and the power cable can be changed.
It also has a line-phase sensor to manage power polarity.

Equipped with a remote terminal, it is possible to turn on / off the power in conjunction with the Luxman control amplifier (C-10, C-9, C-7, etc.).

It features a large 120x100mm power meter with a solid Illuminate brand logo on the top.
The meter circuit uses a discrete configuration to accurately convey the driver's driving status and to ensure smooth movement.
The display method is logarithmic compression type. When monaural is used by BTL connection, the left meter is used.

The front panel uses a 15 mm thick extruded aluminum material with a special pear-shaped finish.
It also features a traditional Luxman design with a wooden cabinet.

There was a version upgrade service from M-10 to M-10II.