High Gain Microphone Preamplifier - 45 to 75 dB gain

  • Low-Noise, High-Gain, Mic Preamp
  • Adjustable Output Levels
  • High or Low Impedance Mic Inputs
  • Mic Input to Line Outputs
  • Two Balanced or Unbalanced Outputs
  • Phantom Capability
  • RF-Filtered Inputs
  • Recommended Power Supply ( Not Included )
    PS-24AS (USA)PS-24AX (International)


    The STM-3 is a quality low-noise microphone preamplifier designed for use in surveillance, commercial sound, broadcast, and recording where higher than normal gain is required. The STM-3 is very flexible, with gain adjustment from 45 to 75 dB, two balanced or unbalanced outputs, and available phantom supply input. Its low-distortion and low-noise performance make it the best choice, even when larger preamps could be used. The STM 3 supply input is single ended and operates from 24 Vdc. Operation from 12 Vdc is possible with a 6 dB reduction in headroom. Each output drives high or low impedance loads.


    Input:500 Ω balanced; 5 kΩ unbalanced
    Phantom:24 Vdc; IEC 61938: 2013, Filtered
    Output (2):+4 dBu 150 Ω balanced; -10 dBV unbalanced
    Frequency Response:50 Hz to 30 kHz (± 1.5 dB)
    Gain:Adjustable 45 to 75 dB
    THD+N: 50 dB (50 Hz to 20 kHz)
    Residual Noise: 20 dB (24 Vdc supply); 14 dB (12 Vdc supply)
    Phantom Power Input:24 Vdc @ 10 mA maximum
    Ambient Operating Environment:0° C to 55° C
    Power Requirement:GROUND-REFERENCED, 24 Vdc @ 25 mA
    Dimensions:Height: 0.7 in. (1.7 cm); Width: 3 in. (7.6 cm); Depth 1.6 in. (3.9 cm)
    Package Type:Cardboard Box
    Package Dimensions:2 x 2 x 4 in.
    Shipping Weight:0.195 lbs.
    WEEE weight:0.145 lbs.
    Tariff code:8543.70.9860

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    CAD FilesUnitsSizeFormat
    Engineering Functional BlockAmerican3.93 KBDXF
    Panel Diagram - EndAmerican3.2 KBDXF
    Panel Diagram - FrontAmerican64.9 KBDXF
    Panel Diagram - EndMetric3.04 KBDXF
    Panel Diagram - FrontMetric66.33 KBDXF
    High Res ImagesFormat
    Declaration of Conformity


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