title: Speech Adjustments for Room Acoustics and Their Effects on Vocal Effort.
abstract: OBJECTIVE
  The aims of the present study are (1) to analyze the effects of the acoustical environment and the voice style on time dose (Dt_p) and fundamental frequency (mean f0and standard deviation std_f0) while taking into account the effect of short-term vocal fatigue and (2) to predict the self-reported vocal effort from the voice acoustical parameters.
  
  
  METHODS
  Ten male and ten female subjects were recorded while reading a text in normal and loud styles, in three rooms-anechoic, semi-reverberant, and reverberant-with and without acrylic glass panels 0.5 m from the mouth, which increased external auditory feedback. Subjects quantified how much effort was required to speak in each condition on a visual analogue scale after each task.
  
  
  RESULTS
  (Aim1) In the loud style, Dt_p, f0, and std_f0increased. The Dt_pwas higher in the reverberant room compared to the other two rooms. Both genders tended to increase f0in less reverberant environments, whereas a more monotonous speech was produced in rooms with greater reverberation. All three voice parameters increased with short-term vocal fatigue. (Aim2) A model of the vocal effort to acoustic vocal parameters is proposed. The sound pressure level contributed to 66% of the variance explained by the model, followed by the f0(30%) and the modulation in amplitude (4%).
  
  
  CONCLUSIONS
  The results provide insight into how voice acoustical parameters can predict vocal effort. In particular, it increased when SPL and f0increased and when the amplitude voice modulation decreased.
authors.affiliation: Voice Biomechanics and Acoustics Laboratory, Department of Communicative Sciences and Disorders, Michigan State University, East Lansing, Michigan. Electronic address: pb@msu.edu.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Bottalico
mesh_terms: D000162:Acoustics; D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D005160:Facility Design and Construction; D005260:Female; D006801:Humans; D008297:Male; D009038:Motion; D010699:Phonation; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013061:Speech Acoustics; D013068:Speech Production Measurement; D013997:Time Factors; D014732:Vibration; D014832:Voice Disorders / Q000503:physiopathology; D014833:Voice Quality; D055815:Young Adult
keywords: Room acoustics; Speech adjustments; Vocal effort; Vocal fatigue; Voice acoustical parameters