Sounders (AAD)

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Addressable Base Sounder


The LASS series Addressable Synchronised Sounders are loop-powered audible alarm devices that plug in to System Sensor analogue addressable detector bases such as the B501AUS.

Each LASS-series alarm device can be individually activated (addressed) by a fire alarm control panel over an analogue addressable loop. In a Pertronic F220 system, the control panel’s loop driver board controls the audible signals.

Tones from all LASS alarm devices connected to a single loop driver can be synchronised, provided that the loop driver is fitted with firmware version 4.08.00 or later. An F220 loop driver can control two analogue addressable loops. So, all LASS devices on a pair of loops can be synchronised.

Two audible alarm tones can be controlled by the fire alarm panel. These tones indicate alarm Stage 1 (Evacuate) and alarm Stage 2 (Alert). The pair of tones may be configured from any one of four optional two-stage tone-sets. The sounder’s alarm is internally synchronised with the audible alarm.

LASS series alarm devices are compatible with the optional anti-tamper feature on the B501AUS and compatible detector bases. When activated, the anti-tamper feature inhibits unauthorised removal of the alarm device. Note that if an LASS device is used with a B501AP deep base, there will be a 3-4 mm gap between the device and the mounting surface. 

The Addressable Synchronised Sounders (LASS-BSO-NC, LASS-WSO-NC) are independently certified as compliant with AS ISO 7240.3:2014.


  • Addressable audible alarm devices
  • Suitable for mounting on wall or ceiling
  • Plug in to B501AUS and compatible detector bases
  • Sounders produce two-stage audible alarm signals synchronised to the audible alarms
  • Two volume settings, configurable by DIP switch
  • Four DIP switch configurable audible tone sets including ISO 8201 temporal pattern (T3) evacuation signals and AS 2220 evacuation and alert signals
  • Field test mode enabled by DIP Switch
  • DIP switches accessible only when the device is not plugged in to a base
  • All LASS devices on a loop pair can be synchronised in Pertronic F220 systems (requires loop driver II firmware version 4.08.00 or later)
  • Compatible with detector base anti-tamper feature
  • Rotary address switches for loop address configuration
  • Base Sounder (LASS-BSO-NC) colour-matched to 200 Series detectors (Ivory)
  • Independently tested and SAI Global StandardsMark certified to AS ISO 7240.3:2014
  • Suitable for retrofit to Pertronic F120A systems using existing detector base(s)

Ordering Information

Product Code



AA Detector Base Sounder, Ivory, Non Isolation, (requires B501AUS Base)

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