PMT Audio
Manley Labs Nu Mu

Manley Labs

Nu Mu

Compressor

From Manley Labs:

The Manley Nu Mu integrates the T-Bar modified all-tube variable-mu input stage from the classic Variable Mu® Limiter with a solid-state output stage. Combining vacuum tube gain reduction characteristics with contemporary circuit performance. Hand-built in California with custom hand-wound Manley IRON® input transformers and Manley Power® supply technology, the Nu Mu delivers reliable, predictable and musical compression and limiting in demanding tracking and mixing sessions.

The Nu Mu's tube-based variable-mu input stage provides smooth compression curves with harmonic characteristics of vacuum tube gain reduction, while the solid-state output path ensures fast transient response and extended bandwidth. This hybrid architecture maintains the dimensional qualities of all-tube compression while delivering the transient accuracy and focused output required for contemporary production across diverse program material.

The proprietary HIP® (High Impact Preservation) control enables compression of low-level signals while maintaining transient peaks, effectively raising quieter content without attenuating dynamic information. This topology achieves results similar to parallel compression through direct signal path processing, adding density and detail resolution while preserving impact and transient definition across vocals, instruments, and mixed program material.

Specs

Tubes
4 x hand-matched 6BA6 vacuum tubes
Inputs
Manley IRON® input transformers; Transformer-Balanced XLR inputs
Power supply
MANLEY POWER® High Voltage Switched Mode Power Supply custom designed for our vacuum tube audio circuits
Features
Manley HIP function raises soft dynamics without squashing louder passages; Continuously variable OUTPUT level controls; Continuously variable THRESHOLD controls; Hardwired Relay Bypass Switch; Stereo Link establishes Left-Master dynamic control for THRESHOLD, ATTACK, and RECOVERY controls; Beautiful illuminated stereo VU meters read Gain Reduction or Output Level
Input level preset
INPUT Level Preset 3-way switches -3dB, 0, +3dB
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)
-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.
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
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)
Transformerless impedance-balanced 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.

Source: Manley Nu Mu product page