Effect of Power Amplifier Distortion on the Speech Transmission Index for Public Address Systems

• Autorzy: Dziechciński Paweł

Identyfikatory

DOI

10.24425/aoa.2022.141649

• Języki publikacji: EN

Abstrakty

EN

The effect of the power amplifier on speech intelligibility in public address systems is often marginalised – i.e. it is assumed that it does not introduce significant signal distortion. This approach is justified when the linear range of the amplifier is used. The large crest factor of the speech signal and economic considerations mean that the amplifier also works in the non-linear range. In this paper, the effect of power amplifier distortion on the speech transmission index for public address systems (STIPA) is presented. In the first step, this influence was evaluated by measurements for Class AB and D amplifiers. Then, a computer model of the public address system based on the direct STIPA method, taking into account the non-linear properties of the amplifier, was proposed. Using the computer model, the optimum amplifier driving values were determined taking into account the reverberation time and interfering noise.speech transmission index; power amplifier; public address system.

Słowa kluczowe

EN

speech transmission index; power amplifier; public address system

• Wydawca: Instytut Podstawowych Problemów Techniki PAN ; Komitet Akustyki PAN ; Polskie Towarzystwo Akustyczne
• Czasopismo: Archives of Acoustics
• Rocznik: 2022
• Tom: Vol. 47, No. 2
• Strony: 191--199
• Opis fizyczny: Bibliogr. 21 poz., rys., tab., wykr.

Twórcy

autor

Dziechciński Paweł

• Department of Acoustics, Multimedia and Signal Processing, Wrocław University of Science and Technology Wrocław, Poland

Bibliografia

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