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Hearing loss can be debilitating. An otherwise healthy individual with a hearing impairment may feel incapable of participating in social events, going to the local super market, or attending church. Fortunately, advances in hearing recovery devices allow even small churches to serve everyone who enters to worship.

An assistive listening system (ALS) is part of the solution for those with minor to moderate hearing damage. An ALS serves as a supplementary device to improve retention of audio information. In public gathering spaces, individuals are given radio receivers tuned to a specific frequency or aimed at an emitter panel. The ALS ties directly into the house sound system to deliver a clear signal to the user's personal receiver.

Assistive listening systems are now inexpensive enough (starting at $800) to be purchased by small congregations, yet they make a serious statement about the church's desire to reach the surrounding community. Larger ministries may be compelled to provide an ALS if they fall under the Americans with Disabilities Act (ADA) guidelines that require public venues to devote a percentage of their capacity to those with special needs.

A typical introductory ALS package contains an FM radio transmitter in the 72 MHz region (below the standard FM radio station transmission range of 88—108 MHz), four to six receivers, and an assortment of earbuds and coil loops to deliver the signal to the wearer.

As an alternative to FM radio transmission, some manufacturers offer systems based on infrared (IR) technology, which work on a line-of-sight basis, as commonly used in TV remote controls. Line-of-sight transmission offers a security advantage over FM since the IR signal will not travel beyond the walls of the room. In addition, with IR transmission you'll have the ability to operate several systems simultaneously within a single building. On the downside, IR requires the user to keep the receiver in view of the transmitter's emitter panel in order to receive clear audio.

A third option is an ALS based on the induction loop principle. With this system, a single loop of wire is placed around the perimeter of a room and excited by an amplifier. Hearing aids with a built-in telecoil (the "T" position) receive the signal and convert it into sound waves. The hearing aid "broadcasts" the audio signal directly into the wearer's ears, allowing noise-free reception of the message.

To configure an ALS, first determine if it will tie into the church sound system or function as a stand-alone system. Using the church sound system as the transmission basis will add tone and dynamic controls to the ALS signal. From an auxiliary output or secondary main output, run a cable to the ALS transmitter's input. Adjust the level until the meter reads zero, and confirm the sound quality through one of the receivers.

On some systems, the receiver and transmitter can select among several frequencies, so make certain they align with one another. If, however, the house sound system is inadequate, a dedicated microphone can be connected to the transmitter and the ALS will function as a stand-alone system.

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