Spectral Analysis Option

The ASTi Integrated Level D Spectral Analysis option is a powerful add-on package to the Telestra system that combines the ability to:

  • Run real-time 1/3" octave spectral band plots of any signal source available within the system
  • Automatically calibrate and compare runtime averaged 1/3rd octave spectral band data captures to original aircraft data recordings under manual or host control.

The results are formatted for direct inclusion into eQTG documentation. This means that no specialized training or audio engineering skills are required to conduct the semi-annual re-qualification of the sound system by the FAA/CAA, etc.


Conventional Level D testing of a sound system requires costly and highly specialized equipment and skilled operators, in order to produce the 1/3rd octave comparison plots required for objective qualification. Couple this with the necessity to further process both the captured data and original recordings in order to generate human readable results, leads to a multi-step process that is complex and subject to operator error and will often create issues with repeatability. In addition, the cost of a conventional sound analysis software package capable of processing the data in this fashion plus a suitable high quality microphone will typically be around $15K.

With the introduction of the Telestra Spectral Analysis option the Level D sound testing task is greatly simplified. Physically, the only external equipment required is the ASTi-supplied measurement class microphone, mic stand, and cable. The cable is connected to a designated audio input of an on-board ASTi ACU2 (ACENet Communications Unit - 2nd Gen). The data generation and capture operations are then controlled from the Telestra web interface Spectral Analysis page or if preferred, the customer host computer.

ASTi's solution is both substantially less expensive and far easier to integrate into an eQTG system.