Audio Technologies Inc. BU400B
Unidirectional 4-Channel Interface Converter with XLR to RCA

OUR PART #  BU400B


The Audio Technologies Inc UB400B is a unidirectional four-channel interface that converts four IHF level signals into four balanced professional outputs. The UB400B is particularly useful in protecting the four, eight or sixteen main or monitoring IHF outputs of low cost mixers and tape decks. The UB400B is also a very low cost way to interconnect two CD players into a balanced system.

Audio Technologies Inc BU400B Features:

  • Quiet, external UL approved 24VDC wall mount power
  • Gold plated RCA type phono jacks
  • Stackable as two or three.
  • Separate LEDs for each 1X4 channel indicate either output clipping (standard) or input signal presence (special order -S)


Audio Technologies Inc BU400B Specifications:

  • Gain: -14db nominal, -8db maximum. +14db nominal,+22db maximum. User adjustable for -10dBu (.25V) User adjustable to 0, +4 or+8dBm output with 0, +4 or +8dBm inputs output with - 10dBu (.25V) input.
  • Nominal Levels: +4dBm input, -10dBu (.25V) out -10dBu (.25V) in, +4dBm out
  • Peak Levels: +22dBm in, +8dBu (2.0V) out +8dBu (2.0V) in, +22dBm out
  • Noise 20kHz B.W.: -90dBu maximum output -80dBm maximum output
  • Harmonic Dist.: .02% Max at Peak Level .02% max. at Peak Level 20Hz to 20kHz .005% max. at Nominal Level .005% max. at NominalLevel
  • Frequency Resp.: +.25dB, 20 to 20,000Hz +.25dB, 20 to 20,000 Hz
  • Crosstalk: 70dB minimum at 10kHz 70db minimum at 10kHz
  • Input Impedance: Balanced, 20kohm bridging Unbalanced 10,000 ohms
  • Output Impedance: Unbalanced, 1500 ohms max. Zs.Balanced, 40 ohms maximum
  • Dimensions: 1.5"H by 5.5"W by 5.75"D; Weight: 1.5 Lbs.Net
  • Connectors: XLR (balanced input/outputs) & RCA phono jacks (unbalanced input/outputs)
  • Power: 24VDC @ .07A - BI100 & UB400, 24VDC @ .04A- BU400,
  • Connector sleeve is positive.
  • Power Supplies: All units require 24VDC power supply, which is ordered separately. They can share a single supply-using loop thru DC cable (P/N20602-1). Do not exceed rated supply current.

Audio Technologies Inc. BU400B
Unidirectional 4-Channel Interface Converter with XLR to RCA

OUR PART #  BU400B

Product Information:

The Audio Technologies Inc UB400B is a unidirectional four-channel interface that converts four IHF level signals into four balanced professional outputs. The UB400B is particularly useful in protecting the four, eight or sixteen main or monitoring IHF outputs of low cost mixers and tape decks. The UB400B is also a very low cost way to interconnect two CD players into a balanced system.

Audio Technologies Inc BU400B Features:

  • Quiet, external UL approved 24VDC wall mount power
  • Gold plated RCA type phono jacks
  • Stackable as two or three.
  • Separate LEDs for each 1X4 channel indicate either output clipping (standard) or input signal presence (special order -S)


Audio Technologies Inc BU400B Specifications:

  • Gain: -14db nominal, -8db maximum. +14db nominal,+22db maximum. User adjustable for -10dBu (.25V) User adjustable to 0, +4 or+8dBm output with 0, +4 or +8dBm inputs output with - 10dBu (.25V) input.
  • Nominal Levels: +4dBm input, -10dBu (.25V) out -10dBu (.25V) in, +4dBm out
  • Peak Levels: +22dBm in, +8dBu (2.0V) out +8dBu (2.0V) in, +22dBm out
  • Noise 20kHz B.W.: -90dBu maximum output -80dBm maximum output
  • Harmonic Dist.: .02% Max at Peak Level .02% max. at Peak Level 20Hz to 20kHz .005% max. at Nominal Level .005% max. at NominalLevel
  • Frequency Resp.: +.25dB, 20 to 20,000Hz +.25dB, 20 to 20,000 Hz
  • Crosstalk: 70dB minimum at 10kHz 70db minimum at 10kHz
  • Input Impedance: Balanced, 20kohm bridging Unbalanced 10,000 ohms
  • Output Impedance: Unbalanced, 1500 ohms max. Zs.Balanced, 40 ohms maximum
  • Dimensions: 1.5"H by 5.5"W by 5.75"D; Weight: 1.5 Lbs.Net
  • Connectors: XLR (balanced input/outputs) & RCA phono jacks (unbalanced input/outputs)
  • Power: 24VDC @ .07A - BI100 & UB400, 24VDC @ .04A- BU400,
  • Connector sleeve is positive.
  • Power Supplies: All units require 24VDC power supply, which is ordered separately. They can share a single supply-using loop thru DC cable (P/N20602-1). Do not exceed rated supply current.
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