WEDNESDAY MORNING, 30 NOVEMBER 2016 LEHUA, 8:00 A.M. TO 9:05 A.M. Session 3aAAa Architectural Acoustics and Speech Communication: At the Intersection of Speech and Architecture II Kenneth W. Good, Cochair Armstrong, 2500 Columbia Ave., Lancaster, PA 17601 Takashi Yamakawa, Cochair Yamaha Corporation, 10-1 Nakazawa-cho, Naka-ku, Hamamatsu 430-8650, Japan Catherine L. Rogers, Cochair Dept. of Communication Sciences and Disorders, University of South Florida, USF, 4202 E. Fowler Ave., PCD1017, Tampa, FL 33620 Chair’s Introduction—8:00 Invited Papers 8:05 3aAAa1. Vocal effort and fatigue in virtual room acoustics. Pasquale Bottalico, Lady C. Cantor Cutiva, and Eric J. Hunter (Commu- nicative Sci. and Disord., Michigan State Univ., 1026 Red Cedar Rd., Lansing, MI 48910, [email protected]) Vocal effort is a physiological entity that accounts for changes in voice production as vocal loading increases, which can be quanti- fied in terms of Sound Pressure Level (SPL). It may have implications on potential vocal fatigue risk factors. This study investigates how vocal effort is affected by room acoustics. The changes in the acoustic conditions were artificially manipulated. Thirty-nine subjects were recorded while reading a text, 15 out of them used a conversational style while 24 were instructed to read as if they were in a class- room full of children. Each subject was asked to read in three different reverberation time RT (0.4 s, 0.8 s, and 1.2 s), in two noise condi- tions (background noise at 25 dBA and Babble noise at 61 dBA), in three different auditory feedback levels (-5 dB, 0 dB, and 5 dB), for a total of 18 tasks per subject presented in a random order. The subjects answered questions addressing their perception of vocal fatigue on a visual analog scale. Babble noise and the order of task presentation increased SPL and self-reported fatigue. The SPL increased when the RT and the auditory feedback level decreased further clarifying how vocal effort changes within various conditions. 8:25 3aAAa2. Relationship of the difference of the speech rate of an announcement at the railway station and the listening impression. Sohei Tsujimura (Structures Technol. Div., Railway Tech. Res. Inst., 2-8-38 Hikari-cho, Kokubunji-shi, Tokyo 185-8540, Japan, [email protected]) The purpose of this study is to clear the influence of the speech rate of an announcement on the listening impression. In this study, a subjective experiment in which the elderly and the young adults participated was conducted in the simulated station. In this experiment, the speech rate of an announcement was varied from 4.5 to 9.5 mora/s at 1 mora/s interval, and subjective evaluations (“Listening difficulty,” “Loudness,” and “Strangeness”) of the announcements were made under three types of background noise conditions (LA 65 dB, 70 dB, and 75 dB). The relationships of the speech rate of an announcement and the subjective evaluation such as “Listening difficulty,” “Loudness,” and “Strangeness” were investigated, and the optimum speech rate of an announcement at the railway station was discussed. As a result, it was suggested that “Listening difficulty” has the lowest evaluation value when the speech rate is 6.5 mora/s or 7.5 mora/s. Furthermore, in this speech rate range, “Strangeness” as an announcement at the railway station was not felt. It was dem- onstrated that the optimum speech rate of an announcement at the railway station is in the range from 6.5 mora/s to 7.5 mora/s. 8:45 3aAAa3. Room acoustics and speech perception: Considerations for the developing child. Lori Leibold (Ctr. for Hearing Res., Boys Town National Res. Hospital, 555 North 30th St., Omaha, NE 68124, [email protected]) What children hear in noisy rooms is not the same thing that adults hear. Despite precocious maturation of the peripheral auditory system, the ability to hear and understand speech in the presence of competing backgrounds sounds is not fully developed until adoles- cence. This talk will review results of behavioral studies of auditory masking in children, with a focus on the development speech per- ception in complex acoustical environments. Data will be presented that support the hypothesis that children’s increased susceptibility to auditory masking relative to adults is related to immature perceptual processing such as sound source segregation and selective attention. Findings from studies investigating the extent to which children benefit from acoustic cues thought to facilitate sound source segregation will be highlighted. 3126 J. Acoust. Soc. Am., Vol. 140, No. 4, Pt. 2, October 2016 5th Joint Meeting ASA/ASJ 3126 WEDNESDAY MORNING, 30 NOVEMBER 2016 LEHUA, 9:20 A.M. TO 12:00 NOON Session 3aAAb Architectural Acoustics and Signal Processing in Acoustics: Advanced Analysis, Simulation, and Auralization in Room Acoustics I Michael Vorl€ander, Cochair ITA, RWTH Aachen University, Kopernikusstr. 5, Aachen 52056, Germany Tetsuya Sakuma, Cochair The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan Toshiki Hanyu, Cochair Junior College, Department of Architecture and Living Design, Nihon University, 7-24-1, Narashinodai, Funabashi 274-8501, Japan Chair’s Introduction—9:20 Invited Papers 9:25 3aAAb1. Can you trust your numeric simulations—How to verify your code and validate your model. Lauri Savioja (Dept. of Comput. Sci., Aalto Univ., PO Box 15500, Aalto FI-00076, Finland, Lauri.Savioja@aalto.fi), Sebastian Prepelita, Pierre Chobeau (Dept. of Comput. Sci., Aalto Univ., Espoo, Finland), and Jonathan Botts (ARiA, Culpeper, VA) In many fields where numeric simulations are utilized, there are standard practices on how to make sure that the simulation results are of high quality. In room acoustic simulations this seems to be quite rare although there are several factors that affect the accuracy of the simulations. First of all, there should be guarantees that the mathematical model, typically partial differential equations, actually 3a WED. AM model the physical phenomena under investigation. This can be made sure by validation and it can take place, for example, by compar- ing the simulation results to some reference solution or to measurement data. This is typically not a concern for the linearized wave equation although adding realistic boundary conditions makes it more challenging. Another essential factor affecting the correctness and reproducibility of the results is the quality of the implementation. Code verification is a procedure that aims to guarantee that an imple- mentation is free of errors. In this paper, we review some common practices of code verification. As a practical example, we show verifi- cation studies conducted with our finite-difference time-domain solver. In addition, we show convergence rates obtained with the same solver to demonstrate the order of the accuracy of the underlying models. 9:45 3aAAb2. Crowd noise simulation system for sound environment evaluation of public spaces. Tetsuya Sakuma (Graduate School of Frontier Sci., The Univ. of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan, [email protected]) and Yukiko Nishimura (Inst. of Technol., Shimizu Corp., Tokyo, Japan) Aiming at the prediction and evaluation of sound environment of public spaces, a simulation-based auralization system is developed for reproducing background crowd noise. The system combines room acoustics modeling using a ray tracing method with a six-channel sound field reproduction system in an anechoic room. As sound sources, footsteps and voices of pedestrians moving on a floor, and HVAC noise from a ceiling are modeled. In a preliminary examination simulating several existing public spaces, a general correspon- dence to real sound field are confirmed in noise level and auditory impressions such as noisiness, liveness, and so on. Next, simulating a variety of imaginary rooms with changing room dimensions, absorption and pedestrian density, a subjective experiment of auditory pair- wise comparisons is carried out. The results show that the noisiness fairly corresponds with the noise level, whereas the feeling of rever- beration does not clearly related to the reverberation time, which may be due to the continuous overlap of sounds. 10:05–10:20 Break 10:20 3aAAb3. Binaural simulation using six channel reproduction based on the finite difference time domain room acoustic analysis. Shinichi Sakamoto (5th Dept., Inst. of Industrial Sci., The Univ. of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8505, Japan, [email protected]), Takatoshi Yokota, and Sakae Yokoyama (Kobayasi Inst. of Physical Res., Tokyo, Japan) For auralization of room acoustics, various simulation-reproduction systems, such as ray tracing, cone tracing, image source meth- ods, and wave-based numerical analysis for sound field simulation, and transaural system, multi-channel loudspeaker system for sound field reproduction, have been developed. As a sound recording-reproduction system, the six channel system has been developed, in 3127 J. Acoust. Soc. Am., Vol. 140, No. 4, Pt. 2, October 2016 5th Joint Meeting ASA/ASJ 3127 which a sound signal is recorded by orthogonally located six directional microphones having a cardioid characteristics and the recorded signals are reproduced by orthogonally arranged six loudspeakers. To obtain binaural signals for auralization with headphones, the six channel reproduction was combined with binaural recording using dummy head microphones. The proposed concept can be efficiently applied to room acoustic simulation. As a room acoustic calculation method, finite-difference time-domain method was employed in this study. The calculated room impulse responses were reproduced by six channel reproduction system, and the binaural signals are recorded using dummy head microphones. In this presentation, the concept of the reproduction system is first stated and some examples on room acoustic problems are introduced. 10:40 3aAAb4. Evaluation of spatial impression of sound field in a concert hall based on the sound intensity using musical sounds. Toshiki Hanyu (Dept.