Convention Paper
Application of Speech Intelligibility to Sound Reinforcement
AES Convention 85 · Paper 2731 · November 1988
Abstract
Sound reinforcement and reproduction systems have grown to a scale where church committees and auditorium owners spend up to $1,000,000 for them. In the past, such systems were purchased without any assurance that acceptable speech intelligibility would be achieved. Today, speech intelligibility can be both specified in advance, designed for, and be objectively measured with accuracy as good as that achieved using a panel of "live" listeners. This article describes the competing techniques, evaluates them, and describes some of the remaining problem areas encountered in analyzing nonstandard systems. The Peutz percent articulation loss of consonants technique (%ALcons), the speech transmission index (STI), and the rapid speech transmission index (RASTI) are all defined, compared to live listener tests made with a large listener sample and illustrated using currently available analyzers.
