Source-Filter Interaction in Speech

描述（由申请人提供）：本研究解决了一个已经存在了半个多世纪的语音产生理论的改进，即源-滤波器理论。它通常用于声学语音学和描述声音和语言障碍。它也广泛应用于语音处理，从声音谐振器中分离声源。语音产生研究的最新进展，主要是通过计算机模拟，表明喉部的主要声源（声门气流）可以受到从声道向后传播到喉部的声压的高度影响。反馈的相互作用可以扰乱声带振动，产生音高跳跃，次谐波频率，甚至混乱。它还可以影响发声阈压，使其更容易或更难以自我维持声带振荡。这项研究的意义在于，某些通常被称为声音障碍的声音品质，可能是人类正常声音清单的一部分。具体目标是(1)确定声音强度是否会受到源-滤波器相互作用（SFI）的影响，(2)发现哪种声道结构会导致最大的相互作用，(3)验证或无效被称为反过滤的程序，据称

DESCRIPTION (provided by applicant): This research addresses refinement of a theory of speech production that has existed for more than half a century, the source-filter theory. It is used routinely in acoustic phonetics and in the description of voice and speech disorders. It is also used extensively in speech processing to separate sound sources from sound resonators. Recent advances in speech production research, primarily with computer simulation, have shown that the primary sound source in the larynx (glottal airflow) can be highly influenced by acoustic pressures propagating backwards from the vocal tract to the larynx. The feedback interaction can disturb vocal fold vibration, producing pitch jumps, subharmonic frequencies, or even chaos. It can also affect the phonation threshold pressure, making it either more easy or more difficult to self-sustain vocal fold oscillation. The significance of the research is that cerain vocal sound qualities, often labeled as voice disorders, may be part of a normal inventory of human sounds. Specific aims are (1) to determine if vocal intensity can be affected by source-filter interaction (SFI), (2) to discover which vocal tract configurations lead to the greatest interactions, (3) to validate or invalidate a procedure known as inverse-filtering, which allegedly separates the source characteristics from filter characteristics, and (4) to determine if vocal instabilities in the aging male voice are related to SFI. Human volunteers and computer simulation will be used in a structured way to quantify and explain the nature of SFI. PUBLIC HEALTH RELEVANCE: Speech production involves both creation of sound and reinforcement of sound. The larynx is the primary sound producing organ, and the airway (vocal tract) is the resonator. It has traditionally been assumed that the two function (and are controlled) independently, one producing pitch, loudness, and voice quality while the other produces vowels and consonants. It is investigated in this research whether or not this independence always exists. The airway structure (shape) may influence the production of sound in the larynx, creating loudness and pitch changes, as well as instabilities that are perceived as roughness and uncertainty in control. Some of these instabilities are observed in aging voices.