Integrated amplifiers — Luxman L-509X

The Luxman L-509X is the top solid-state integrated amplifier from the Japanese company and continues a line of top integrated models that began with the L-509fSE in 2002. Luxman describes it as separates in a single unit. It combines the volume control of the C-900u preamplifier and an output stage modelled on the M-700u power amplifier in one chassis, together with an MM/MC phono stage, tone controls and a headphone output. White-lit analogue meters and a hairline-finished top panel follow Luxman's classic styling.

Key specs that matter

Output is 120W per channel into 8 ohms and 220W into 4 ohms from a bipolar four-parallel push-pull Class AB stage, with a damping factor of 370. THD is 0.007% or less at 1kHz and 0.06% or less from 20Hz to 20kHz. Line signal-to-noise ratio is 105dB, and phono S/N is 91dB (MM) and 75dB (MC). Inputs are four line (180mV, 47 kilohms), two balanced (180mV, 55 kilohms), MM phono (2.5mV, 47 kilohms), MC phono (0.3mV, 100 ohms) and main in (1.1V, 47 kilohms), with record out, pre-out, monitor connections and A and B speaker terminals. Line response reaches 100kHz (-3dB) and phono response is 20Hz to 20kHz (+/-0.5dB). Bass and treble adjust by +/-8dB. Power consumption is 380W, or 150W at idle. The chassis is 440 x 193 x 463mm, weighs 29.3kg and comes with an RA-17A remote.

Engineering and use context

The New LECUA1000 attenuator from the C-900u is integrated with the preamplifier's gain stage rather than placed ahead of it, switching precision resistor networks electronically so the channels track closely at every setting. LECUA also handles the balance control. The power amplifier uses ODNF 4.0, Luxman's fourth-generation distortion-only feedback with a triple-paralleled error-detection stage, followed by a three-stage Darlington driver and four parallel pairs of output transistors per channel, the same layout as the M-700u, which keeps output rising into 4-ohm loads. The supply pairs a 600VA EI-core transformer with independent left and right filter capacitor banks totalling 80,000 microfarads. Wiring from the amplifier boards to the terminals uses thick 3.5 square-millimetre cable, and a loop-less chassis structure keeps ground impedance low. Pre-out and main-in let the preamplifier and power sections be used separately.

Pairing

High current output and damping let it drive demanding floorstanding speakers. The phono stage takes MM and MC cartridges directly, and the A/B terminals allow bi-wiring or two pairs of speakers.

Alternatives

The Luxman L-507Z is the smaller integrated model below it in the range, with lower power output.