The Role of Psychoacoustic Factors in Sound Source Localization

Öz

The human auditory system utilises on complex psychoacoustic mechanisms to perceive the direction and distance of sound sources in the environment. This study, derived from the theoretical framework chapters of the doctoral dissertation titled “Analysis and Improvement of Listener Position Induced Distortions in Stereo Sound Systems,” examines, within the context of spatial hearing, the fundamental factors influencing sound source localization namely interaural time difference (ITD), interaural intensity difference (IID), and head related transfer function (HRTF) through a theoretical perspective. Based on a comprehensive literature review, the perceptual functioning of these phenomena is explained using mathematical models, and the role of dynamic cues resulting from head movements is also evaluated. The study separately addresses the impact of acoustic behaviours such as reflection, refraction, and interference of sound waves, as well as anatomical features like the head and pinna, on auditory perception. In addition, the limitations of non individualised HRTF data and accuracy issues in localising sound sources in both virtual and real environments are discussed. The findings reveal significant implications for enhancing spatial accuracy of sound in virtual reality (VR) and augmented reality (AR) systems. The study establishes a theoretical foundation for achieving more precise sound localization across various disciplines, including sound engineering, acoustic design, and auditory interface applications.

Anahtar Kelimeler

• Psychoacoustics
• Sound Localization
• Spatial Audio
• Binaural Hearing
• Sound Modelling

Ses Kaynağı Konumunun Tespitinde Psikoakustik Faktörlerin Rolü

Öz

İnsan işitme sistemi, çevredeki ses kaynaklarının yön ve mesafesini algılamak için karmaşık psikoakustik mekanizmalardan faydalanmaktadır. “Stereo Ses Sistemlerinde Dinleyici Konumu Kaynaklı Bozulmaların Analizi ve İyileştirilmesi” başlıklı doktora tezinin kuramsal çerçeve bölümlerinden üretilen bu çalışma, uzamsal işitme kapsamında ses kaynağı konumunun tespitinde etkili olan kulaklar arası zaman farkı (ITD), kulaklar arası şiddet farkı (IID) ve kafa ilişkili aktarım fonksiyonu (HRTF) gibi temel faktörleri teorik bir çerçevede incelemektedir. Literatür taramasına dayanan bu araştırmada, söz konusu fenomenlerin algısal işleyişi matematiksel modellerle açıklanmış, ayrıca dinleyici baş hareketlerinden doğan dinamik ipuçlarının lokalizasyondaki rolü değerlendirilmiştir. Çalışmada, ses dalgalarının yansıma, kırılma, girişim gibi akustik davranışları ile baş ve kulak kepçesi gibi anatomik özelliklerin ses algısına etkileri ayrı ayrı ele alınmıştır. Bunun yanı sıra, bireyselleştirilmemiş HRTF verilerinin sınırlılıkları ve sanal/gerçek ortamlarda ses kaynağı konumlandırmadaki doğruluk sorunları tartışılmıştır. Elde edilen bulgular, özellikle sanal gerçeklik (VR) ve artırılmış gerçeklik (AR) sistemlerinde sesin uzamsal doğruluğunu artırmaya yönelik önemli çıkarımlar ortaya koymaktadır. Çalışma, ses mühendisliği, akustik tasarım ve işitsel arayüz uygulamaları başta olmak üzere birçok disiplinde ses lokalizasyonunun nasıl daha doğru modellenebileceğine dair teorik bir temel oluşturmaktadır.

Anahtar Kelimeler

• Psikoakustik
• Ses Konumlandırma
• Uzamsal Ses
• Binaural İşitme
• Ses Modelleme

Kaynakça

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