Stewart Audio PA50B


The Stewart Audio PA-50B is a 2 channel half rack amplifier - 25W x 2 @ 8 Ohm.

The PA Series was specifically designed to meet the rigorous requirements of Sonic Accuracy, High Efficiency, Low Power consumption and extended duty cycles all in a very compact Half Rack Package. Low cost, lightweight and convection cooling make this amplifier perfect for high quality commercial, industrial and Pro Audio sound installations. Our flexible design allows bridging to mono for increased power and will also accept balanced or unbalanced signals by way of 1/4" TRS input connectors. With thousands in operation across a broad range of applications, this hardworking Class AB amplifier has passed the test of time again and again.

Stewart Audio PA-50B Features:

  • Compact Half Rack Package
  • Two Channel Amplifier, Optimized to drive 4 / 8 Ohm
  • Convection Cooled (No Fans)
  • Clean Full–Range Dynamic Power
  • World Class Reliability

Stewart Audio PA-50B Specifications:

  • 8 Ohm Stereo Power: 25W
  • 4 Ohm Stereo Power: 50W
  • 8 Ohm Bridged Power: 100W
  • Frequency Response (+0, -0.5 dB, 1W): 20Hz - 20kHz
  • Power Bandwidth (+3, -3dB): 5Hz - 100kHz
  • THD+N: <.1%
  • Signal to Noise Ratio: >100dB  
  • Slew Rate: 30V/microsecond
  • Input Sensitivity: 1V (0 dBV)
  • Standard Voltage Gain: 40x (32dB)
  • Input Impedance (Balanced/Unbalanced): 20k Ohms
  • Idle Current Draw, 1/8 Power Draw: 0.13/0.56A
  • Class: AB
  • Input Connectors: TRS
  • Output Connectors: Terminal Strip
  • Power Supply: High-speed Switching
  • Cooling: Convection-Cooled (No fans)
  • Controls: Power, Channel Gain
  • LED Indicators: Power and Clip
  • Construction: Steel and Aluminum Chassis
  • Dimensions (H x W x D): 1.75 x 8.2 x 6.2"
  • Weight: 3.5lbs
  • Warranty: 3 years

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