STI (Speach Transmission Index) intelligibility measures have largely replaced ALCons as the preffered method of measuring intelligibility. Both EASE and EASE Jr now project STI using MTI (Modular Transfer Index) data projections in accordance with IEC Standard 60268-16:2003. Projections are available for both open spaces and closed rooms.

A typical STI Map for a room with poor intelligibility is shown below.

EASE and EASE Jr then calculate RaSTI and other intelligibility measures from the STI data. See menu window show below. Note the wide range ofmeasures available.