The new top-of-the-line Luxman C-10X control amplifier incorporates the Luxman Electronically Controlled Ultimate Attenuator-EX (LECUA-EX) and Luxman Integrated Feedback Engine System (LIFES-1.0), both making their premiere in a preamp.
The C-10X replaces the earlier C-900u and complements the latest M-10X power amplifier and D-10X digital player. Other key advances include four preamplifier blocks that operate in fully balanced configuration; LECUA-EX control including tone shaping options; and a robust chassis with three-dimensional layered front panel.
The C-10X control amplifier is available immediately at a suggested retail price of $19,995.
Luxman Electronically Controlled Ultimate Attenuator-EX
Unassuming and often overlooked, volume control can be the source of subtle and not-so-subtle sonic degradations. Conventional, variable-resistor volume controls often introduce noise. And left/right tracking errors can unintentionally shift the stereo balance as the user adjusts volume. For these reasons, Luxman has long avoided the variable resistor in favor of carefully crafted attenuator circuits. The LECUA-EX is a computerized precision attenuator using a rotary encoder separate from the signal path. To enhance the experience, a weighted damping mechanism enables smoother adjustment with a satisfying tactile “feel.”
The C-10X incorporates Luxman’s most advanced version of LECUA-EX, providing meticulous volume adjustment across 192 discrete steps from 0 to 95.5 dB, while minimizing distortion and noise. Unique to the C-10X, the LECUA-EX system also adjusts left/right channel balance (from L –6 dB to R –6 dB), adjusts each bi-amp output level (±6 dB), and adjusts input offset (0 to –6 dB) to equalize the volume among different sources.
Luxman Integrated Feedback Engine System (LIFES-1.0)
The C-10X is the first control amplifier to incorporate the LIFES-1.0 circuit, the latest expression in Luxman’s multi-decade quest to overcome the long-standing tradeoffs in amplifier negative feedback. Negative feedback has always been a double-edged sword. While feedback plays a central role in reducing distortion, even minuscule inaccuracies in its application can compromise the expressive power of music reproduction. It was to overcome this paradox that Luxman created the Only Distortion Negative Feedback (ODNF) circuit in 1999 and refined it through five generations up to 2021. LIFES-1.0 supersedes even these achievements, with a completely redesigned discrete circuit featuring improvements in distortion detection, regulation, and thermal stability. The result is a rare combination of exceptionally low distortion and the natural sound quality associated with “non-feedback” circuits.
Circuitry refinements
The internal layout is dominated by four preamplifier blocks that provide a direct fully balanced signal path from balanced inputs to balanced outputs. The four maintain identical operational states for ultimate sound quality. The 15 dB gain accommodates a range of associated components, compared to 12 dB in the predecessor C-900u. For exceptional voltage stability, the power supply incorporates a high-capacity CI core transformer and an array of seven custom-designed 3300 µF filter capacitors. Internal wiring uses Luxman original oxygen-free copper cable with special wrap shielding for each non-plated copper wire. In classic Luxman fashion, even the printed circuit boards are thoroughly engineered, utilizing peel-coat solder mask to minimize dielectric effects and 100 µm thick, gold-plated circuit traces while the non-angled wiring pattern ensures smooth current transmission. Unbalanced inputs and outputs employ original 27-mm pitch RCA terminals while balanced connections use Neutrik XLR connectors.
Operational refinements
For versatile operation, the three line inputs offer balanced terminals with input phase select in addition to unbalanced jacks. Likewise, the C-10X supports bi-amping with two preamp outputs, both available through balanced or unbalanced terminals. The LECUA-EX attenuator system provides input level matching, left/right channel balance, and bi-amp output level setting — all in addition to master volume control. A preamp input accommodates an external source such as an AV system. The volume-linked loudness control facilitates proper tonal balance during quiet listening. Control input/output terminals support daisy-chain operation with compatible equipment. The 12-volt trigger terminals work with third-party control systems. The supplied RA-20 aluminum remote control includes muting function.
Chassis and design refinements
The loop-less chassis eliminates the effect of rising ground impedance. Large, density-gradient cast iron feet suppress shelf-borne vibration. The substantial front panel features the same side-bevel design as the matching M-10X power amp and D-10X digital player. The top panel features a classic Luxman hairline finish. Finally, the front-panel fluorescent display offers both dimming and 4X zoom display magnification for easy IR volume control adjustment when the operator is situated at a distance from the main unit.
For more information, visit luxmanamerica.com.
