We are the practitioners of audio on behalf of the house of worship. Our job is to provide all the technical support necessary to ensure that all those who attend our church (in person or remotely) will indeed hear all that should be heard. We have a substantial amount of control over the technology that will be used to accomplish this task — we get to choose our equipment, and we get to decide how it will be deployed and configured, and when our services commence, we actively adjust it to achieve the best results.
Helping Those in Need
There is one factor in the process over which we have no control, however. We have no control over the physiological capacity for our parishioners to hear the sound that we present. Some people are born with diminished hearing, and others have lost hearing acuity over the course of their lives. In fact, long-term attrition in hearing is something that all of us humans face over time. But if we were to presume that almost all our hard-of-hearing parishioners are seniors who were born in the early to mid-20th century, we may be wrong.
Unfortunately, in the modern world, hearing degradation seems to be faster than ever, with damage to the hearing of young people resulting from a seemingly unavoidable cacophony of industrial noise and the high-SPL entertainment they consume. Hopefully they’ll do better going forward protecting their hearing, but for now, it just feels like a lot of them are making poor choices.
Whether young or old, diminished hearing is an issue with which us pro audio types must contend. It’s such an important issue that government entities have deemed it worthy of legislation to help resolve it. The Americans with Disabilities Act spells out requirements for certain entities to provide solutions to help improve the auditory experience for the hard-of-hearing. And while houses of worship are exempt from these laws in most states, I would respectfully submit that it is incumbent upon us to serve our fellow human beings and go out of our way to ensure that the sounds are heard by all — not just those blessed with healthy ears to hear. Let’s look at how we can go about this.
RF and Infrared Solutions
A common assistive listening modality is RF, and with good reason. We’ve been doing radio for about 125 years now, and we’ve got a pretty good handle on it. In terms of hardware, it’s pretty simple — we need a receiver for each parishioner who will be using assistive listening, and we’ll need a transmitter to feed these receivers. We may need multiple transmitters or a distributed antenna system to ensure consistent coverage throughout our space. And as with all small, unobtrusive tech gadgets, there is a tendency for the receivers to “walk away,” forgotten in a pocket or a purse or some such, so invariably we must assign someone (or multiple “someones”) to administer the distribution — and collection — of these devices. The fact that we must provide these receivers and keep track of them is one of the few drawbacks of choosing RF. Among the benefits of RF is its inherent lack of audible latency — the signal is heard immediately — and this is not true for all options. As we will see, this latency can be problematic.
Infrared (IR) is another modality that does not exhibit audible latency. In fact, because the audio is distributed to congregants on a carrier wave of light, it arrives even faster than radio waves. It does, however, share the same drawback as RF, in that a receiver must be assigned to each attendee who seeks assistive listening, and multiple receivers must be administered. It has yet other drawbacks, namely that IR transmission must be line-of-sight (unlike RF, which can permeate objects in our space). This could increase the necessary financial investment because we may need additional IR emitters to ensure that the entire space is covered. But as RF bandwidth continues to shrink and suffer intermodulation challenges, IR can still be an attractive alternative.
Another RF-based option for assistive listening is a loop system. This is similar to RF because it distributes our signal via electromagnetic energy. A copper loop (either wire or tape) snakes its way around our space, typically embedded either in the floor or ceiling, and creates an electromagnetic field that inductively creates current in a device known as a telecoil (or “T-coil”) that is either part of a parishioner’s hearing aid system or can be connected to that system. The telecoil passes our signal along to the hearing aid system, directly delivering sound to the user. It’s particularly nice if the user’s hearing aids have built in telecoils, but unfortunately, that’s not always the case. If no telecoil is present, an external telecoil device must be used to feed the signal to the hearing aid system, and in this case, we’re really no better off than with an RF or IR system, which also require a receiver device. Nevertheless, loop systems remain in use around the world.
The Smart Phone / Wi-Fi Approach
The final assistive listening modality we’ll examine is Wi-Fi. This mechanism is appealing because it can be substantially less expensive than others — essentially only requiring the deployment of Wi-Fi routers through which our signal can be sent. Of course, the signal must be digital, and this could be a challenge for churches that are still using a completely analog system, but it is not insurmountable. The big advantage with Wi-Fi is that most attendees will have a smart phone that can be used by them as a “receiver.” They can connect to Wi-Fi and “tune in” to a URL through which the signal can be heard. It would still require headphones or earbuds, and of course not every parishioner will have a smart device, but maintaining a small handful of tablet devices is probably comparable in price to maintaining RF receivers. One drawback of Wi-Fi is the signal latency. If we’re delivering substantial SPL through our FOH speakers, it could be heard by an assistive listening user, combining with the slightly delayed Wi-Fi signal, and creating phase incoherencies or even perceived echo if the latency is substantial.
A Dedicated Mix
We have learned that when we provide a livestream of our services, whether via radio broadcast or online, we must take care to provide a mix that presents the entirety of what the in-person congregation hears. In many (maybe even most) churches, acoustical energy from drum kits, on-stage instrument amps, and other sources is heard directly by the parishioners, and our FOH mixer balances that SPL with the output of our FOH loudspeakers to arrive at a perfect blend. Those who are listening via livestream only hear what is captured by microphones or DIs, so there may be an imbalance — the drums and amplified guitars, for example, may be under-represented in the stream mix. It is for that reason that I strongly recommend a discrete mix for streaming — literally mixed on a separate console in an isolated room if possible. The great news here is that this very same mix can be sent to our assistive listening devices to ensure that those folks also hear the entire blend.
Providing assistive listening is the right thing to do, whether we’re forced to do so by law or not. In terms of how to go about it, we have options, and our budget and degree of technical sophistication should provide guidance as to which we should deploy.
John McJunkin is an adjunct professor at Grand Canyon University
