Product Details


Shure PA421B Antenna Combiners are complementary accessories for Shure PSM Personal Stereo Monitor systems. When multiple systems are required for monitoring environments, the PA421B combiners quietly and efficiently reduce rack clutter and optimize RF management for up to four PSM®900 transmitters or two PSM®1000 transmitters when racked in a central location.

Note: PA421B replaces PA421A.


  • Combines multiple PSM transmitters to a single antenna set
    • Improves RF networking
    • Reduces rack clutter
  • Wideband operation (470–865 MHz or 865–960 MHz)
  • 4 Input LED Signals (green when active; off when inactive)
  • Quieter fan for significant reductions in ambient unit noise
  • Temperature-sensitive fan power for significant reductions in ambient unit heat
  • Provides DC power to compatible IEM transmitters
  • LED indications of signal presence and signal overload
  • Passive (non-powered) antenna combining*

* Contact Shure Service Department for more detail and availability. Requires modification of unit by qualified service technician.

Available Options

PA421B Four-port PSM Antenna Combiner, 470–865 MHz (United States & Canada)
PA421BX Four-port PSM Antenna Combiner, 865–960 MHz (United States & Canada)

Software & Downloads

Specification Sheets

File Language Type File Size
PA421B Specification Sheet English PDF 551 kb

User Guides

File Language Type File Size
PA421B and PA821B User Guide PDF 10.7 mb

Product Support

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