RDL ST-UMX3 3x1 Universal Audio Mixer

The ST-UMX3 is a three-channel audio mixer for combining mic-level or line-level signals to a single output. A MIC/LINE switch is provided for each input. A separate MIC/ LINE switch selects the output level. Each input features a separate preamplifier circuit, which isolates it from the other inputs. An audio taper single turn gain adjustment is provided for each of the three input preamps. Signals from the three preamps are actively summed and fed to the output amplifier which includes an RDL® dual-LED VU meter.

Each input level is set while observing the LED output level meter. The dual-LED output meter follows standard VU ballistics. The intensity of the green LED progresses from minimum at -11 dBu to full intensity at +4 dBu.

The flexibility of switching each input and the output between MIC or LINE allows installers to address a wide variety of mixing solutions with only one product type.

RDL ST-UMX3 Features

• Audio Mixing with Up To Three Inputs
• Switch-Selectable Mic or Line Inputs
• Switch-Selectable Mic or Line Output
• Add Additional Microphone or Line Level Inputs to an Existing Mixer
• Combine Signals of Different Level, Impedance, or Balanced /Unbalanced Configuration

• ST-UMX3 3x1 Universal Audio Mixer1

• Inputs (3)
  • Mic: 600 Ω; Line: 50 kΩ, balanced
  • NOTE: MIC INPUTS ON ST-UMX3 ARE NOT PROTECTED AGAINST PHANTOM VOLTAGE. USE THE ST-MPA24 or ST-MPA48 MIC PHANTOM ADAPTER.
• Maximum Input SignalMic: -18 dBu; Line: +25 dBu
• Gain (each input)
  • Mic: Adjustable from OFF to 60 dB
  • Line: Adjustable from OFF to 21 dB
• Output150 Ω balanced; 75Ω unbalanced
• Output Signal
  • Mic: 50 dB below line level
  • Line: +4 dBu nominal
• THD+N< 0.006%
• IMD
  • Mic (@ 50 dB gain): < 0.04%
  • Line: < 0.008%
• Freq. Response
  • Mic: 50 Hz to 100 kHz (± 1 dB)
  • Line: 10 Hz to 100 kHz (± 0.05 dB)
• Noise (each input)
  • Mic: < -70 dB (50 dB gain)
  • Line: < -82 dB (unity gain)
• Headroom18 dB
• CMRR
  • Mic: > 60 dB
  • Line: > 50 dB, (50 to 120 Hz)
• Ambient Operating Environment0° C to 55° C
• Power RequirementGROUND-REFERENCED, 24 Vdc @ 55 mA
• Package Dimensions2 x 2 x 4 in.
• Shipping Weight0.175 lbs.
• WEEE weight0.12 lbs.