The SoundOut room acoustics analyser is a free to download iPad application, developed at NAL, tailored to the needs of educational institutions. It offers an easy way to measure classroom background noise level, classroom ambient noise level, classroom Reverberation Time (RT) and Speech Transmission Index (STI).

Based on the measured results, general recommendations are given to teachers/school about possible solutions that would help address certain noise problems and improve the classroom acoustics in general. A “traffic lights” style indicator is used to flag the results in three categories: acceptable result = green light; borderline result = amber light; unsatisfactory result = red light. The criteria for these categories are based on reviews of published works. Measurement records are automatically saved on the iPad for review.