Manley MNUMU Nu Mu Stereo Limiter Compressor

Vendor: Manley
Manley MNUMU Nu Mu Stereo Limiter Compressor The Manley MNUMU is professionally designed Featuring a hybrid tube/solid-state design, switchable input levels, and Manley IRON balanced-input transformers, the Nu Mu is made as a...

Manley MNUMU Nu Mu Stereo Limiter Compressor

The Manley MNUMU is professionally designed Featuring a hybrid tube/solid-state design, switchable input levels, and Manley IRON balanced-input transformers, the Nu Mu is made as a dual-channel compressor and limiter that's made suitable for use on the stereo buss. The unit itself comes stocked along with the same tube front-end of the well regarded Variable Mu—four hand-matched 6BA6 vacuum tubes on the valve side—and at the same time it is offering a FET solid-state amplifying and output stage, which is capable of providing a faster, punchier path. As such, it’s a compressor well suited for electronic pop productions, or other mixes where one is desiring a more transparent stereo-buss compressor, rather than a color piece.

The Nu Mu is capable of providing an output controls designed for both the left and right channels, as well as independent bypass, ratio, threshold, attack, and recovery selectors. Both the attack and recovery settings are made continuously variable, reacting to the music pumped through the channels. Still, you are able to roughly dictate how slowly or quickly these controls operate. You’ll note the independent three-position toggle switches, which are dictating the input level, giving you a choice of +3, 0, or -3 dB. Separate VU meters can be configured to read gain reduction or overall output levels.

On the left of the unit, you’ll find a link button, which will turn the left channel into the master channel, thereby ganging threshold, attack, and recovery controls. In this way, you can achieve a cohesive stereo picture when processing a dual-channel source. On the right, you’ll note the HP SC switch, which operates the internal sidechain detector circuit, factory set to 100 Hz. This global control is useful for allowing bass signal to pass through the NU MU without triggering gain reduction, thereby securing yourself a fuller, more bass-heavy sound.

The unit provides two different ratios, one offering compression at approximately 3:1, and the other offering limiting at 10:1—or thereabouts; the ratio, like the attack and recovery times, is program dependent.

Perhaps the most interesting feature of this unit is the Hip control, accessible on the right side of the front panel. When engaged, the Hip control does not operate as hard on intrinsically louder signals as it does on audio with a lower amount of level, effectively allowing your louder material to shine through uncompressed. Using this circuit can obviate the need for parallel compression in certain situations. The unit takes up 2 RU of rack space and comes with its own power supply.


  • Variable attack and release controls, which can be set between slow and fast
  • 2 ratios for compression or limiting
  • Hip control for preserving dynamics of loud sections
  • Suitable for use as a stereo-buss compressor on electronic production, or other material where clean, punchy gain-reduction is called for
  • 4 x hand-matched 6BA6 vacuum tubes with FET solid-state amp and output stage
  • Stereo link establishes left-master dynamic control
  • Illuminated stereo VU meters read gain reduction or output level
  • High-voltage SMPS custom designed for Manley Labs' vacuum tube audio circuits

  • Manley IRON® input transformers

  • 4 x hand-matched 6BA6 vacuum tubes

  • Balanced XLR inputs & outputs

  • Manley HIP function raises soft dynamics without squashing louder passages

  • MANLEY POWER® High Voltage Switched Mode Power Supply custom designed for our vacuum tube audio circuits

  • INPUT Level Preset 3-way switches -3dB, 0, +3dB

  • Continuously variable OUTPUT level controls

  • Unity Gain set INPUT to "0" and OUTPUT control to 11 o’clock. (Input source Z= 150 Ohms, Output load Z= 100 kOhms)

  • Maximum input level: (1 kHz Sine, <0.3% THD+N)
    -3 = +25 dBu
    0 = +21 dBu
    +3 = +18 dBu

  • Maximum GAIN: 13dB

  • GAIN makeup: 10dB (gain above unity)

  • Output Headroom: 23dB (referenced to +4dBu)

  • Variable ATTACK control: 13msec - 130msec

  • RECOVERY switch 5 steps: 0.1s, 0.16s, 0.32s, 0.64s, 1.7sec.

  • Continuously variable THRESHOLD controls

  • Hardwired Relay Bypass Switch

  • Ratio Mode switches between LIMIT (1.5:1 to 12:1) or COMPRESS (1.2:1 to 3:1)

  • HP SC: High Pass Side Chain Filter -3dB @ 100Hz @ 6dB per Octave

  • Stereo Link establishes Left-Master dynamic control for THRESHOLD, ATTACK, and RECOVERY controls

  • Beautiful illuminated stereo VU meters read Gain Reduction or Output Level

  • Sidechain INSERT per channel via 1/4" TRS jack TIP=SEND, RING=Return, SLEEVE=Ground

  • Maximum Output: +27dBu (18Vrms) into 100K Ohm load; +24.5dBu (13Vrms) into 600 Ohm load. (1Khz Sine, < 0.3% THD+N, BW 20Hz - 20kHz).

  • Frequency Response: - 0.8dB @ 20Hz, -0.5dB @ 50kHz

  • Total Harmonic Distortion: <0.05% THD+N (1kHz Sine, +4dBu, BW: 20Hz - 22kHz)

  • Noise floor: -85dB typical (BW: 20Hz - 22kHz)

  • Dynamic Range: 112dB

  • Signal to Noise Ratio: 89dB (referenced to +4dBu)

  • Common-Mode Rejection Ratio (CMRR): 74dB (BW: 20Hz - 22kHz, +4dBu, 1kHz Sine)

  • Output Impedance: 100 Ohms

  • Input Impedance: -3dB= 1 kOhms, 0dB= 2.5 kOhms, +3dB= 4.5 kOhms

  • AUTOMUTE warmup delay: 30 Seconds

  • Power consumption: 35 Watts

  • Standby Power Consumption: 0.5 Watts

  • Operating mains voltage: 90 to 254 VAC (internal universal supply)

  • Mains Voltage Frequency: 50-60Hz

  • Dimensions: 19" x 3 1/2" x 7" (occupies 2u)

  • Unit Weight: 8.5 lbs.

  • Shipping weight: 11.5 lbs.