The Luxman M-900u stereo power amplifier is another masterpiece from Japanese engineers at Luxman. The design of the model is made in the style of minimalism: clear and smooth lines, an understandable control system and massive gradient supports that protect the device from unwanted vibration – this is what you can notice at first glance at the model.
Aesthetically, the Luxman M-900u power amplifier is made in a laconic retro style. The model boasts impressive power ratings, as well as the ability to work with any acoustic systems.
The Luxman M-900u amplifier has a massive 48-kilogram case with a front aluminum panel, which has two arrow level indicators with original white LED backlighting. On the facade there is a power/standby button with an indication of operating modes, an input selection button with two LEDs, a backlight off button and an LED diode indicating the activation of the BTL bridge mode. The amplifier chassis does not use a ground loop, which can introduce parasitic interference and noise. The case has excellent damping and rests on gradient cast-iron legs that effectively dampen resonances and vibrations. The
Luxman M-900u power supply is equipped with four capacitors with a capacity of 20,000 μF and a powerful transformer (1250 VA), the windings of which are made using wires with a rectangular cross-section. A thick busbar made of purified OFC oxygen-free copper runs from the power supply to the output stages. The device develops a power of 150 W per channel at 8 Ohm, 2 x 300 W at 4 Ohm and can operate in the BLT bridge mode, delivering 600 W (8 Ohm). Up to 12 W, the Luxman M-900u operates in class A. The Luxman M-900u amplifier has a damping factor of 710 units and is not afraid of load impedance drop down to 1 Ohm.
Each channel of the amplifier has one block with four parallel push-pull amplification circuits. Darlington circuits and proprietary ODNF negative feedback technology (version 4.0), developed specifically to suppress distortion, are used. Premium-class components are used in the circuits.
There are two inputs on the rear part of the amplifier – balanced and unbalanced. One of the connectors of each input can be used to connect the Luxman M-900u in monoblock mode (bridge), for switching to which the corresponding “slider” is used. For balanced connectors, there is a switch that inverts the phase. There is a port for connection via the system bus and a ground terminal. For connecting the speaker system, the power amplifier is equipped with two pairs of massive screw terminals.
The amplifier’s sound is characterized by openness, exceptional purity, naturalness, rich natural highs and mids, deep dense bass and a wide voluminous stage. The model will be an excellent companion for working in tandem with the Luxman C-900u preamplifier.
Luxman M-900u Specifications
Nominal output power 2 x 150 W (8 Ohm); 2 x 300 W (4 Ohm); 600 W (8 Ohm) in bridged mode (mono)
Peak output power 2 x 1200 W (1 Ohm); 2400 W (2 ohms) in bridged mode (mono)
Input voltage 1.24 V (180 W, 8 ohms)
Gain 29 dB
Input impedance 34 kOhm (XLR), 51 kOhm (RCA)
Frequency response 20 Hz – 20 kHz (+ 0, – 0.1 dB), 1 Hz – 130 kHz (0, – 3 dB)
Total harmonic distortion less than 0.008% (1 kHz, 8 ohms), less than 0.1% (20 Hz – 20 kHz, 8 ohms)
Signal-to-noise ratio 117 dB
Damping factor 710
Inputs balanced XLR (with phase switch), unbalanced RCA
Other switching system bus socket, ground terminal Speaker
output 2 pairs of screw terminals
Power supply EI transformer (1250 VA), 4 capacitors each 20000 μF
Power consumption 540 W; 280 W without signal; 1 W in standby mode
Dimensions (WxHxD) 440x224x485 mm
Weight 48 kg