Manley STEREO VARIABLE MU (B-Stock)

Vari-Mu Stereo Limiter Compressor for Mastering

• Stereo tube reference compressor/limiter for mastering
• B-Stock version: product tested and fully functional
• All-valve circuit with Variable Mu® technology
• Musical and transparent compression ideal for mix bus and mastering
• Selectable COMPRESS and LIMIT modes
• Custom Manley transformers with extended frequency response
• Side-chain with built-in high-pass filter
• Variable attack, recovery and threshold controls
• Stereo links for precise management of final mix

Manley Variable Mu: reference tube compression for mastering

The Manley Stereo Variable Mu is one of the most iconic limiter compressors in the world of professional audio mastering. Used in countless successful productions, this tube processor represents an absolute standard for those seeking musical, elegant and highly transparent compression.

B-Stock version: guaranteed Manley quality

This unit is available in a B-Stock version, fully functional and verified, offering Manley sonic excellence at a more affordable price. Ideal for professional studios that want to integrate high-end hardware into their setup.

Variable Mu® technology: natural and musical compression

At the heart of the system is Variable Mu® technology , based on re-biasing the tubes to achieve extremely smooth gain reduction. This approach, shared with legendary vintage compressors such as the Fairchild 670, keeps the musicality of the signal intact even with major interventions.

COMPRESS and LIMIT modes for every need

The Variable Mu offers two operating modes:

• COMPRESS: 1.5:1 soft-knee ratio for gentle and musical compression
• LIMIT: from 4:1 up to 20:1 for sharper dynamic control

Perfect for mix bus and mastering

With stereo link management and precise dynamic control, the Manley Variable Mu excels in mix bus, 2-track, and final mastering applications. The result is a unique sonic cohesion, often described as a "cream" that envelops the mix.

Valve construction and high-quality components

The all-valve circuit uses select components and Manley proprietary transformers with nickel laminations, ensuring extended frequency response and superior sound quality.

Technical Specifications.

• Type: Stereo tube compressor/limiter
• Version: B-Stock
• Circuit: fully tube (5670, 5751, 7044/5687, 12AL5 per channel)
• Inputs/Outputs: balanced (600 ohms)
• Transformers: custom Manley with 20Hz - 25kHz response
• Modes: COMPRESS (1.5:1), LIMIT (4:1 to 20:1)
• Attack: variable from 25 ms to 70 ms
• Recovery: 5 steps (0.2s, 0.4s, 0.6s, 4s, 8s)
• Threshold: continuously variable
• Side-chain filter: HPF -3dB @ 100Hz
• Maximum gain: 35 dB
• Maximum output: +30 dBu
• THD: <0.1% @ 1kHz
• Noise floor: about -85 dB
• Stereo link: yes
• Bypass: hard-wire
• Power consumption: 80W
• Power supply: 100V / 120V / 220-240V selectable
• Dimensions: 19" x 3.5" x 10" (2U)
• Weight: approx. 10.4kg