Mark Levinson #523: 6-input dual mono Pre-amplifier

The Mark Levinson № 523 is a 6-input dual mono amplifier that features Pure Path circuitry, a Class A Pure Phono section, and adjustable balanced, single-ended, and Main Drive Headphone Class A outputs for driving headphones up to 32 ohms from the...

Mark Levinson #523
Mark Levinson #523

The Mark Levinson № 523 is a 6-input dual mono amplifier that features Pure Path circuitry, a Class A Pure Phono section, and adjustable balanced, single-ended, and Main Drive Headphone Class A outputs for driving headphones up to 32 ohms from the main circuit.

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The Mark Levinson № 523 preamplifier features five line-level analog inputs: two balanced (XLR) and three unbalanced (RCA), plus a Pure Phono input (RCA with ground pin). The preamp provides balanced (XLR) and unbalanced (RCA) stereo outputs, as well as a Main Drive Headphone output for 6.3 mm headphones on the metal front panel – a first for Mark Levinson. In terms of system integration, it is available via Ethernet/IP networking, RS-232, USB connection for web-based control and configuration, plus 12V triggers and an infrared (IR) input. The supplied machined metal remote control provides the precision control and rugged feel that befits this preamplifier.

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The Pure Phono section features a MM (Moving Magnet) subsection with five capacitive driver loading settings and an MC (Moving Coil) subsection with three preamplification settings and 10 resistive driver loading settings. The Main Drive Headphone amplifier circuit drives headphones up to 32 ohms from a Class A amplifier circuit, using the main output chain rather than a secondary signal path: an excellent example of reducing redundancy in the circuit design. A

selectively enabled fourth-order high-pass filter at 80 Hz allows transparent integration of a single subwoofer or dual subwoofer configuration and excellent performance across all frequencies over a wide range of speaker configurations. A discrete and balanced R-2R volume control for precise and efficient operation ensures uncompromising performance regardless of the analogue source.

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Like all Mark Levinson products, the #523 is designed and hand-assembled in the USA. Mark Levinson’s engineering research and development is conducted at the company’s dedicated Engineering Center for Technology Excellence in Shelton, Connecticut, while in neighboring Massachusetts, the Mack Technologies factory in Westford is home to the team of skilled craftsmen who create all Mark Levinson equipment and carry out small-scale production.

Mark Levinson #523 Specifications

Linear section gain, at normal gain settings: 13.5 dB balanced; 7.5 dB unbalanced
Frequency Response Linear Section, 20 Hz to 20 kHz: ±0.02 dB
Frequency Response Linear Section, 0.4 Hz to 370 kHz: +0.1 / -3 dB
Total Harmonic Distortion+Noise @ 1 kHz (2 Vrms unbalanced or 4 Vrms balanced output): <0.003%
Signal-to-Noise Ratio (ref. 2 Vrms unbalanced or 4 Vrms balanced, max volume): >115 dB @ 1 kHz
Crosstalk @ 1 kHz: <-107 dB
Channel Separation: Below Noise Floor (>115 dB @ 1 kHz)
Input Impedance: >45 kΩ
Output Impedance: <80 Ω unbalanced, <160 Ω balanced
Maximum Input Level, at Normal Gain Settings: >10Vrms, unbalanced, >15Vrms, balanced
Maximum Output Level: >11Vrms, unbalanced, >22Vrms, balanced
Headphone Output Impedance: Switchable; <3Ω or 75Ω
Maximum Headphone Output, Low Impedance Mode, 30Ω (0.3W), 20Hz to 20kHz, <0.1% THD: >3Vrms
Maximum Headphone Output, Low Impedance Mode, 300Ω, 20Hz to 20kHz, <0.1% THD: >9Vrms
Headphone THD+N, 20Hz to 20kHz, 2Vrms: <0.03% at 30Ω, <0.01% at 300Ω

Phono Section

RIAA Frequency Response: 20Hz to 20kHz, ±0.3dB
Subsonic Filter: Switchable, 15Hz, 2 orders (12dB/octave)

Moving Magnet Mode MC

Input Impedance: 47 kΩ
Input Capacitance: Switchable; 50,100, 150, 200 or 680 pF
Gain: 40 dB at 1 kHz
THD+N, 20Hz to 20kHz, 2Vrms: <0.03%

Moving Coil Mode MM

Input Impedance: Switchable; 20,33, 50, 66, 100, 200, 330, 500, 1000, or 47 kΩ
Input Capacitance: 50 pF
Gain: Switchable; 50, 60, or 70 dB at 1 kHz
Total Harmonic Distortion+Noise, 20Hz to 20kHz, 2Vrms: <0.02% for 50 or 60dB settings, <0.04 for 70dB setting

Inputs/Outputs

Analog Inputs: 2 balanced (XLR), 3 unbalanced (RCA) line level, 1 unbalanced (RCA) turntable input with ground lift
Analog Outputs: 1 balanced (XLR); 1 pair unbalanced (RCA), 1 headphone (¼ inch, 6.3 mm TS)
Control connections: Ethernet (RJ45), RS-232 (RJ12), trigger in and out, IR in, USB-A, Mini-USB

Power: 100 VAC, 115 VAC, or 230 VAC (factory set)
Power consumption: 0.4 watts in green standby, 5 watts in power save mode, 67 watts in normal standby, 75 watts in on idle mode

Dimensions: Height (with feet): 10.2 cm, Width: 43.8 cm, Depth: 45.7 cm
Net weight: 17.7 kg