A minority of hearing aid owners concurrently use ALDs. About 1 in 4 consumers use a phone amplifier, while less than 10% of hearing instrument owners are users of ALD devices for enhancing their hearing with TV, at movies, in places of worship, or in conferring.
ALDs “stretch” the performance of a hearing aid by increasing the signal to noise ratio (SNR). This is significant as SNR has to be higher for many people with hearing loss for them to hear speech over background noise ALDs reduce the effect of distance between the person with hearing loss and the sound source; override poor acoustics; and minimize background noise.
There are hard-wired ALDs and three types of wireless ALDs (audioloop, FM, and Infrared). All three types can be used with or without hearing aids and can be used with an array of receiver attachments for consumers with varying needs and preferences. This includes neck loops, silhouette inductors, headphones, direct audio input and other linkages. Hard-wired ALDs include hand-held amplifiers with microphones, direct audio input microphones, and hard-wired systems.