Manley Backbone Mastering Insert Switcher


A little history: we have been building custom mastering consoles for many many years, since the early 1990's. You can view some of these custom creations on our Custom Mastering Console Page. But as we know, custom design work is both expensive and time consuming so we drew upon our experience to create a new stock production Mastering Insert Processor, the Manley BACKBONE.

The MANLEY BACKBONE accepts up to three balanced SOURCE INPUTS, selectable on the left side. LEFT & RIGHT can be reversed and ABSOLUTE POLARITY can be flipped. The 24 position INPUT & OUTPUT GAINS can be switched active or left passive. Up to EIGHT INSERTS can be switched in or bypassed. A SUM - DIFFERENCE MS MATRIX can be addressed between inserts 2 and 3. The order of inserts 4 & 5 can be SWAPPED. There is an injection point between inputs 7 & 8 to allow for several functions on the 3-Function MIX - FADE output control. You can mix in the DIFFERENCE signal from the input. This mixes in some out of phase signal from the input to the output in order to widen the image if desired. OR you can mix in a parallel signal in between inserts 7 & 8. A lot of folks run a reverb or parallel compressor in this fashion. OR you can use the knob as a FADER to make smooth and accurate level fades with the Penny & Giles rotary fader.

The MANLEY BACKBONE is available with ELCO or DB25 connectors for the INSERTS I/O. Cables for either system are not included and must be custom made or ordered.


  • 3 x Balanced Stereo Inputs
  • 8 x Balaced Stereo Inserts
  • Selected Input can be mixed to parallel outputs
  • Patchable SEND and RETURN
  • Balanced signal path all the way
  • Left - Right Reverse Switch
  • Absolute Polarity Reverse Switch
  • Bypass GAINS makes passive signal path
  • Over 90 nice relays employed
  • EAO switch buttons can be easily custom labeled
  • INPUT and OUTPUT GAINS use 4 x 24 position Grayhill switch attenuators
  • SUM - DIFFERENCE (MS Matrix) can be used for Inserts 2 & 3
  • Separate SUM and DIFFERENCE outputs available on rear panel
  • SWAP order button can be used to reverse the order for Inserts 4 & 5
  • MIX - FADE injection between 7 & 8 with mode select
  • Expensive Penny & Giles rotary fader/mixer
  • I/O Inserts connection system can be ordered with ELCO or DB25 (you choose)
  • Bulletproof MANLEY build quality. But of course!



  • Frequency Response: ± 0.1 dB, 10Hz-100KHz
  • THD + Noise @ +4 dBu input level: 0.0015% A-WGT
  • THD + Noise @ +22 dBu input level: 0.0011% A-WGT
  • IMD60 4:1@ +4 dBu input level: 0.0017%
  • IMD60 4:1@+22 dBu input level: 0.0035%
  • Crosstalk Rejection: ≥ 95dB @ 1 kHz between Gains and Mix-Fade Stages
  • Crosstalk Rejection: ≥ 70db @ 1Khz at SUM-DIF stage
  • Common Mode Rejection: ≥ 100dB @ 100Hz; ≥ 95dB @ 1KHz; ≥ 80dB @ 10KHz
  • Noise floor: -95 dBu, Bandwidth 22Hz-22KHz A-WGT
  • Maximum Signal Level: +28dBu
  • Dynamic Range: 124dB
  • Input Impedance: 30K ohms
  • Output Impedance: 150 ohms
  • Input/Output Stepped Gain Switches accuracy: +/- 0.05dB
  • Power Consumption: 60 watts
  • Mains Fuse: 1A @ 100~120VAC; 0.5A @ 220 ~ 240VAC
  • Mains Fuse type: 5mm x 20mm SLO-BLO GDC glass fuse, 250V AC rating
  • NOTE: Operating mains voltage: Units are purpose built for original destination country's mains voltage: 100V, 120V, or 220-240VAC as indicated on the serial number badge. The power transformer in this unit must be rewired in order to change mains operating voltage.
  • Unit Size: 19" x 10" x 3.5" (occupies 2u) Note: add 5" behind unit for cable allowance
  • Unit Weight: 13 lbs.
  • Shipping Weight: 19 dim. (international); 17 lbs. (USA)
  • Shipping Box Dimensions: 23" x 15" x 9"

Specifications subject to change because they just might.