Functionality and flexibility for airborne loudspeaker systems.

AEM’s industry-leading LSC22 is the most advanced controller available. We qualified it to DO-160G and DO-214 to assist with integration and designed it for pin-for-pin replacement of the AA21, eliminating the need to change wiring harnesses.

Our LSC22 is compatible with both legacy AEM and NAT public address equipment, as well as our new LSA series product line; it also provides wail and yelp siren types which can be customized to suit specific operational requirements.


  • Integrates easily with the aircraft audio system
  • Front panel AUX input jack
  • On-the-fly message recording and playback
  • 25-watt internal speaker amp
  • Front-mount AUX input enables broadcasting of recorded messages from an MP3 player or smartphone
  • Optional NVIS-compliant lighting


  • DO-160G
  • DO-214
  • STC’d


Mechanical Specs
Height 1.11"
Width 5.77"
Length 6.32"
Weight 1.30 lb (max)


LSC22 Loudspeaker Controller


Maximize performance and reliability of your aircraft’s loudspeaker system.

AEM’s AA21-400 Cabin PA and Siren Controller is a single, panel-mounted unit that provides a simple interface to all generations of AEM’s loudspeaker amplifiers and speakers. It maximizes the performance and reliability of your aircraft's PA system with state-of-the-art design, improved frequency response, and an optimized microphone input circuit. 

Integrators will appreciate the AA21-400's simple interface with existing aircraft audio systems. We also made the unit configurable to receive either radio or CD audio, allowing for radio rebroadcast capability or playback of recorded information. 


  • Optimized microphone audio input circuit
  • Field-adjustable audio inputs
  • Selectable wail and yelp siren
  • 25-watt internal speaker amp
  • Available in standard configurations or customized panel layouts, with 5 Vdc or 28 Vdc standard white lighting,
  • Optional NVIS lighting


  • D0-160D
  • DO-170
  • TSO-C50c


Mechanical Specs
Height 1.12"
Width 5.75” at the front, 4.97” at the rear
Length 6.33” excluding mating connectors
Weight 1.4 lb. (max)


AA21-4xx Series Controller

Product Documentation

Product Details Request Form

If you have a capability requirement that isn’t met by an existing system, AEM is open to new opportunities that meet the demands of both fixed- and rotary-wing aircraft. We work with flight crew, integrators, and OEMs to deliver solutions for today’s avionics market.

Tell us what you need.

Type of Inquiry: