December 28, 2020

Classroom audio distribution systems (CADS) can help all students hear better in the classroom, especially during the COVID-19 pandemic, according to a new resource from the Educational Audiology Association. Written for school administrators, educators, and parents, the article  provides evidence-based information on the adverse effects of face coverings on the speech signal,  defines CADS and its benefits, and offers ideas for funding sources.   

CADS were already being used pre-pandemic because amplifying a teacher’s voice has been widely documented as a strategy to improve classroom acoustics (see the ASHA Practice Portal page on Classroom Acoustics). However, with the pandemic requiring teachers to wear face coverings when teaching students in person, teachers are acutely aware of how challenging it is for all students to hear the intended message.  

The class-wide benefit

CADS use a wireless microphone worn by the teacher (or other talkers in the classroom). The microphone transmits the teacher’s voice to the speaker(s), which broadcasts the signal to the students in the classroom.   

Imagine trying to listen to a presentation in a large room with the presenter attempting to project her voice, but you cannot clearly hear them. If you added a CADS system to this scenario, you would understand the speech of the presenter better and with less listening effort. With face coverings and greater physical distance, everyone is struggling to hear and understand speech. The challenge is compounded by any competing sound, such as other people talking, heating/air conditioning units, and other extraneous noise in the environment. When a teacher uses a CADS, his or her voice is amplified and distributed equally to all the students in the classroom.   

Some of the most vulnerable listeners are preschool and school-age children. Regardless of their hearing status, children (especially younger than 11–12) have immature auditory systems. The effects of face coverings plus distance causes a degraded speech signal and reduced access to visual cues, leading to reduced access to the spoken message. The use of CADS in the classroom will improve auditory access to the speech signal and improve students’ access to learning. 

Pass on the knowledge

Beyond CADS, the Ida Institute and NIDCD offer tips for communication during the pandemic. These include speaking clearly and distinctly, being patient with other communication partners, and minimizing extraneous background noise.

Sharing and posting these communication strategies in schools may help remind everyone that, while important to communication and learning any time, they are especially relevant now. For questions about CADS or general questions about classroom listening during a pandemic, reach out to your local educational audiologist.  

Anita Vereb, PhD, CCC-A, is an audiologist with Michigan Medicine’s Pediatric Audiology Department and Cochlear Implant Program and provides educational audiology consultant services to Washtenaw Intermediate School District. She is an affiliate of ASHA Special Interest Group 9, Hearing and Hearing Disorders in Childhood.  [email protected]

Mike Macione, AuD, CCC-A, is an educational audiologist with the Jackson County (Michigan) Intermediate School District and a past president of the Educational Audiology Association. He is an affiliate of SIG 9. [email protected]            

Donna Smiley, PhD, CCC-A, is a supervisor with the EARS Program at Arkansas Children’s Hospital. She is an affiliate of SIG 9. [email protected]       

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