Boys Choirs in the Pandemic: Effects of Distance and Other Factors on Spectral and Temporal Accuracy.

During the Covid-19 pandemic, choral singing has been either completely prohibited or regulated with safety measures due to increased transmission risks. However, the impact of larger inter-singer spacings on the performance and educational process in boys' choirs is unclear. This study analyzed recordings of six groups of five singers each from two boys' choirs aged 7-16 who sang Beethoven's Ode to Joy while standing on an arc with a 4 m radius and an inter-subject spacing of 0.5-3 m. The effects of singers' masks, distance, group age, and relative position on the timing of articulation and fundamental frequency were investigated, along with the amount, rate, and sign of pitch drift and loudness. The ANOCOVA results showed that onsets were robust to the tested factors, while errors in fundamental frequency tended to decrease with increasing age/experience. Loudness was affected by distance, mask, and relative position, with increasing loudness as spacing decreased. Understanding influencing factors can inform recommendations for choral singing and education.

Boys Choirs in the Pandemic: Exploring Qualitative Aspects of Safety Measures.

INTRODUCTION: During the Covid-19 pandemic, choirs had to apply safety measures such as distances and wearing masks. For children's choirs, there is no knowledge of their reaction to these measures, regarding their age and experience. This study aimed to investigate boys choir singers' perceptions of the measures, regarding wellbeing and feasibility, as well as the quality of the performance outcomes. METHODS: Six groups were put together, assembling five singers of the same age (7-16 years, before voice change) and experience level. The boys sang one verse of the same song at inter-subject distances of 3, 1.5, 0.5, 0.5 m plus wearing a mask and again 3 m. Afterward they filled out questionnaires concerning difficulty, irritation, hearing themselves and their neighbors, and if they could imagine singing regularly in the respective setting. Fifteen parents were asked to fill out questionnaires about their opinions about choir safety measures during the pandemic. Six anonymous boys choir experts rated the randomized recordings of all tasks regarding homogenous sound quality, rhythmical precision, and uniform intonation. RESULTS: Even though most of the children preferred smaller distances, they were open to all kinds of settings. The answers given were very specific to the individuals. Masks were voted out by a majority of the subjects. Parents found choir singing very important for their children and did in majority neither fear infection of their children, nor mind precautions. The experts rated the performance outcomes of the largest distance (3 m) as best in most of the cases. CONCLUSION: Different interspatial settings do not harm the children and adolescents and could be introduced as a beneficial approach to give them a broader listening experience and to make them flexible, alert, adaptable, and resilient singers. Singers' masks are only recommended for compelling circumstances.

Aerosol Dispersion During Different Phonatory Tasks in Amateur Singers.

INTRODUCTION: Due to increased aerosol generation during singing, choir rehearsals were widely prohibited in the course of the CoVID-19 pandemic. Most studies on aerosol generation and dispersion focus on professional singers. However, it has not been clarified if these data are also representative for amateur singers. METHODS: Nine non-professional singers (four male, five female) were asked to perform five tasks; speaking (T+), singing a text softly (MT-) and loudly (MT+), singing on the vowel [ə] (M+) and singing with a N95 mask (MT+N95). Before performing the tasks, the singers were asked to inhale 0.5 L vapor produced by an e-cigarette consisting of the basic liquid. The spread of the exhaled vapor was recorded in all three dimensions by high-definition cameras and the impulse dispersion was detected as a function of time. RESULTS: Regarding the median dispersion to the front, all tasks showed comparable distances from 0.69 m to 0.82 m at the end of the tasks. However, the maximum aerosol dispersion showed a larger variety among different subjects or tasks, respectively. Especially in the M+ task a maximum distance of 1.96 m to the front was reached by a single subject. Although singing with a N95 mask resulted in a slightly increased median dispersion to the front, the maximum dispersion was decreased from 1.47 m (MT+) to 1.04 m (MT+N95). CONCLUSION: The maximum dispersion distance to the front of 1.96 m at the end of the M+ task and 1.47 m at the end of the MT+ task showed higher values in comparison to professional singers. Differences in phonation, articulation and mouth opening could lead to greater impulse dispersion. Singing in loud phonation with a N95 mask reduced the maximum impulse dispersion to the front to 1.04 m. Taking all results into consideration, a slightly larger safety distance should be necessary for non-professional singers.