Live streaming has become a very popular broadcast medium. Even more so now in the age of COVID-19 social distancing and limited gatherings. Houses of Worship are being forced to live stream services in order to stay connected with their congregations. A professionally live streamed service is no easy task. There are many technological challenges and acoustics can be the most difficult to overcome especially in highly reverberant or “echoey” sanctuaries.
Reverberation = Bad Broadcast Audio
Live streaming is broadcasting through the internet typically consisting of video and audio or just audio. Audio quality is always a top priority. When it comes to broadcast audio, it is all about eliminating sonic artifacts. A sonic artifact is sound or noise that is unwanted. Reverberation is the prolongation of sound caused by sound reflecting off hard reflective surfaces in architectural spaces. Reverberation is measured from the initial sound until the sound decays 60 decibels or in layman’s terms, when you cannot hear it anymore. In most broadcast environments, reverberation entering a broadcast microphone is a sonic artifact. Reverberation has an adverse effect on direct sound. Reverberation interferes with direct soundwaves reducing clarity and intelligibility. This is bad for any direct acoustic energy turned into electric energy. The sonic artifact is now part of the direct sound which is almost impossible to remove during a live broadcast.
How to Minimize Sonic Artifacts
If you have ever seen a professional broadcast studio, the studio is filled with acoustical treatment. Acoustical treatment is porous sound absorbing material. Acoustical treatment is used to cover hard reflective surfaces such as walls and ceilings to reduce reverberation. In general, the more hard reflective surfaces covered, the lower the reverberation time of the space. The top priority of professional broadcast audio is clarity and intelligibility thus little to no sonic artifacts can exist. Acoustical treatment is the best way to reduce unwanted reverberation to create clean intelligible audio.
Congregations with Happy Ears
This is not only true for broadcast but also for in person services. The lower the reverberation time of a sanctuary the more intelligible and clearer amplified audio will be. A reverberation time of between 1-1.5 seconds would be ideal for in person and live streamed services. Most broadcast studios have a reverberation time south of .5 seconds. Getting a reverberation time that low in a sanctuary would be costly and unnecessary. Spaces with reverberation times less than .5 are considered “dead” spaces. Unless the space is small, a reverberation time of less than .5 seconds feels unnatural and for some, uncomfortable.
Fabric wrapped panels (FWP’s) are the best way to treat a house of worship sanctuary and fellowship hall to reduce reverberation and create an acoustically comfortable in person and broadcast space. We’ve just scratched the surface in this blog post. If you want to learn more about acoustics or have any other acoustical questions, call our Acoustical Solutions professionals at (800) 782-5742. Please visit https://fuse-tg.com/fuse_webcast.pdf to learn more about renting a live streaming technology package and remember to mention that Acoustical Solutions referred you.