ODNF* Version 4.0 – innovative amplification feedback circuit

An integral part of the design of the L-509X is LUXMAN’s original ODNF* amplification feedback circuit, featuring a high-speed primary slew rate, an ultra-wide bandwidth and a low level of distortion that is achieved by feeding back only the distorted components of the audio signal from the output of the amplification circuit. The L-509X is equipped with the latest Version 4.0 ODNF providing a dramatic enhancement of accuracy in distortion detection due to the triple-paralleled first-stage error detection circuit. Lower impedance and a higher signal-to-noise ratio have been achieved due to the paralleled first stage and Darlington-equipped second stage amplification circuit. A 3-stage Darlington circuit and a 4-parallel push-pull structure is used for the output stage, similar to the M-700u power amplifier. This achieves output at 120W+120W(8Ω) and 220W+220W(4Ω), enabling the L-509X to drive speakers powerfully with rich dynamics and full expression. *ODNF stands for “Only Distortion Negative Feedback”.

The chassis structure exemplifies excellence in function and design

The L-509X features a top panel with a beautiful hair-line finish and widened venting to improve heat dissipation. The loop-less chassis structure restricts any increase in ground impedance. Analogue level meters, illuminated with white LEDs, add to the elegant and stylish appearance.

An abundance of user-friendly functions

The L-509X is equipped with a high-quality phono amplifier, compatible with MM and MC cartridges. This model offers all the functions that a high-quality integrated amplifier should, including bass and treble tone controls, L/R balance adjustment controlled by LECUA, pre/power separation function, volume control and headphone output, all integrated into a single unit without compromising sound quality.

Copper alloy terminals

High-quality RCA terminals, made of copper alloy, are used for the LINE-1 inputs of the L-509X, combining the beneficial conductivity of copper and the durability of brass. The L-509X features many custom-made components befitting a flagship model, such as the robust power supply and high-grade speaker terminals that are compatible with Y-connectors.

Gradation cast-iron feet

Thorough vibration countermeasures have been taken, using cast iron feet with a density gradient to eliminate resonance. The high-grade, aluminium body remote control is also supplied as standard.

High-stability power supply

The highly stable power supply circuit developed for the L-509X features a 600 VA EI-core-type power transformer and independent left and right channel large capacity blocking capacitors (10,000μFx4 per channel). This generous custom specification ensures that the power supply unit will not be affected by any load fluctuation.

Discrete buffer circuit

The L-509X is equipped with a discrete buffer circuit that is equivalent to the type used in the high-end LUXMAN C-900u separate amplifier. The clarity of the audio signal is preserved by this circuit whilst at the same time the following power amplification stage’s driving force is significantly increased.

Prioritizing audio quality in design

The use of crack-resistant peel-coat PCBs for the amplifier boards prevents the quality of audio signals from being adversely affected. This product prioritizes audio quality in features such as the non-angled, direct wiring pattern, known as the original LUXMAN’s Beeline construction, ensuring smooth signal transmission via the optimum shortest route.

Increased damping factor

Large-capacity, low-resistance speaker relays are connected in parallel, enabling loss-less transmission of the powerful driving force that is generated by the generous power supply circuit and the amplifier output section of the L-509X. The use of 3.5mm2 cabling for the amplifier board output and the unit’s damping factor of 370 enables the L-509X to drive all kinds of speakers accurately.

New LECUA*1000 computerized attenuator

LUXMAN’s New LECUA1000 is at the heart of the preamp section and the volume adjustment control of the L-509X. This computerized attenuator is integrated with the amplification circuit, a feature integral to the high-end LUXMAN C-900u control amplifier. LECUA provides an ideal level control system which allows smooth and fine adjustment of the volume over 88 steps, thereby minimising the deterioration of audio quality at any point of the volume adjustment range. The advancement of the New LECUA1000 is the 3D design layout. The attenuator circuit board is directly connected to the amplification circuit board. Signal routing has been minimized and efficiency has been successfully enhanced. In addition, this design is extremely resistant to external vibration and eliminates changes in audio quality over the volume control range. The robust nature of this system ensures longevity and durability. *LECUA stands for “Luxman Electronically Controlled Ultimate Attenuator”.