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Sonifex RB-LI2 - Stereo Line Isolation Unit (used)

by Sonifex
£150.00 inc. vat
£125.00 ex. vat
In Stock - Available for Immediate Dispatch

Sonifex RB-LI2 - Stereo Line Isolation Unit - Used

This Used Sonifex Redbox RB-LI2 Stereo Line Isolation Unit is in good condition with a few minor marks. 

The Sonifex RB-LI2 stereo line isolation unit is used to isolate audio signals from inter-area ground hum loops, which could be caused by equipment being powered by different mains power supplies, or different phases on the same supply. The input and output are connected together through a transformer, which has internal jumpers allowing the outputs to be balanced about ground.

We may have multiple of this unit and conditions of units may vary, before purchase please confirm the unit pictured is the unit for sale. Updated pictures can be provided. If you don't chat with us prior to purchase we can not guarantee you will receive the unit pictured.

There is also a loop-through output, so that the RB-LI2 can be inserted into a line, forming a transformer balanced distribution point. 

The isolated outputs can be individually adjusted using pre-set potentiometers, accessible through the rear panel. The gain range of the stereo line isolation unit is -15dB to +13.5dB (28.5dB).

This unit is useful where audio is required to be driven over a relatively long length of cable. By isolating the signal using transformers, ground loop currents that can be present in non-isolated signals, are eradicated completely.

Sonifex RB-LI2 Specification

Audio Specification

  • Output Impedance: <150Ω
  • Distortion: 0.5% THD @ 40Hz, ref +17dBu output
  • Common Mode Rejection: <64dB typically
  • Frequency Response: 10Hz to 36kHz ±0.5dB 
  • Output Gain Range: -15dB to +13.5dB   


  • Inputs: 2 x XLR 3 pin female (Balanced)
  • Isolated Outputs: 2 x XLR 3 pin male (Balanced)
  • Loop Outputs: 2 x XLR 3 pin male (Balanced)
  • Mains Input: Filtered IEC, switchable 110-120V, or 220-240V, fused, 6W max
  • Fuse Rating: 
    • Anti-surge fuse 100mA 20 x 5mm (230VAC)
    • Anti-surge fuse 250mA 20 x 5mm (115VAC)      

Physical Specification

  • Dimensions:
    • 28cm (W) x 10.8cm (D) x 4.2cm (H) (1U)
    • 11” (W) x 4.3” (D) x 1.7” (H) (1U)
  • Weight:
    • Nett: 1.1kg Gross: 1.5kg
    • Nett: 2.4lbs Gross: 3.3lbs