Интегральные усилители — Luxman L-509Z

The Luxman L-509Z is a transistor integrated design made by the Japanese company Luxman, rated at 120 W per channel into 8 ohm and 220 W per channel into 4 ohm. It combines a line preamplifier, an MM and MC phono stage, headphone outputs, tone controls and a power stage inside a case 440 mm wide that weighs 29.4 kg.

Key specs that matter

Line inputs accept 180 mV at 47 kilohm unbalanced or 79 kilohm balanced, and a main input takes 1.1 V at 47 kilohm, while the pre output supplies 1 V. The phono section offers three settings - MM at 2.5 mV and 47 kilohm, MC-H at 0.3 mV and 100 ohm, and MC-L at 0.1 mV and 40 ohm. Line frequency response runs from 20 Hz to 100 kHz within -3 dB, and phono response from 20 Hz to 20 kHz within 0.5 dB. Total harmonic distortion is 0.007 percent at 1 kHz and 0.03 percent across 20 Hz to 20 kHz into 8 ohm. Signal to noise ratio is 106 dB for line, 87 dB for MM, 70 dB for MC-H and 62 dB for MC-L. Damping factor is 330. Consumption reaches 390 W in operation, 150 W with no signal and 0.5 W in standby. The case is 193 mm high and 463 mm deep including knobs and terminals.

Engineering and use context

Amplification follows the LIFES 1.0 system, whose feedback works on the distortion components only and is applied to the final stage. The output stage is built from bipolar transistors in three-stage Darlington form, arranged in a quadruple-paralleled push-pull arrangement. A 600 VA EI transformer feeds large filter capacitors of 10,000 microfarad x 8. Level control relies on the LECUA-EX electronic attenuator in 88 steps from 0 to 87 dB, shown on a 7-segment LED display. Tone controls cover bass, middle and treble with a range of 8 dB each, the middle band aimed at voices and lead instruments. Large needle VU meters have LED backlighting. Headphone sockets are provided in 6.3 mm and 4.4 mm sizes with independent left and right grounding for balanced cables. The RA-17A remote control is supplied.

Pairing

Two sets of large speaker terminals can be switched on and off independently, which allows bi-wiring. The two-step MC gain switch lets both low-output and higher-output moving coil cartridges be connected without an external step-up device, and the pre output gives a route to bi-amping with an extra stereo power unit.

Alternatives

The Luxman L-507Z is the smaller Z-series integrated, delivering 110 W into 8 ohm with LIFES 1.0 feedback, its own moving magnet and moving coil phono section, and output devices in triple-parallel form.