Modern Hearing Aid Features Hearing aids of every sort work in the same basic way with the same basic components. There are four basic parts: microphone, amplifier, receiver, and a battery. Modern digital hearing instruments also include a computer chip capable of precise programming and processing. Sound enters the microphone of the aid, and the signal is converted from acoustic (sound) signals to electrical signals. The amplifier boosts the signal strength, and sends the signal to the receiver (tiny loudspeaker). The receiver transforms the signal back into an acoustic signal and sound is sent through the outer ear canal to the ear to be heard! The addition of a digital computer chip to this process allows for very precise control of the amplification and sound conversion. Digital options have allowed for more sophisticated hearing instrument features. Current, modern hearing instruments are brimming with wonderful features to improve the owner’s hearing life. Below is a short discussion of many of the features available to patients purchasing hearing instruments today. Adaptive Feedback Cancellation is available in most aids to prevent that high-pitched squealing that emits from the aid. Modern digital hearing instruments have an automatic mechanism that detects the presence of feedback, and prevents it. While this Peninsula Hearing Center (619) 569-1937 San Diego, CA (858) 768-0454 La Jolla, CA
feature prevents feedback caused by covering the aid, it will not correct a poorly fit hearing instrument. Automatic Gain Control is a feature that allows the output (the sound you hear through the aid) to be controlled in a way that loud sounds will not be too loud. This feature compresses loud sounds, and can be programmed in such a way as to prevent loud sounds from exceeding a patient’s level of loudness discomfort. Wide Dynamic Range Compression (WDRC) adjusts the incoming sounds to fit into a patient’s specific dynamic range (from the softest heard to a level of loudness discomfort). The signal is compressed at the point of entry into the hearing aid rather than adjusting the outgoing sound signal. The goal is to make soft sounds audible, moderate sounds louder, and loud sounds loud, but not intolerable. If proper WDRC programming is completed, volume adjustments by the user may be unnecessary! Digital Signal Processing is used in almost all modern hearing instruments, requires less space, and allows for very specific user-based programming and customization. Additional programmable features are available with this type of processing, and great success has been found for many patients! Digital Noise Reduction capabilities analyze the incoming sound signal and help determine which sounds are speech-like and which are more noise-like. Much noise tends to be very broadband and steady state, while speech is variable.
Peninsula Hearing Center (619) 569-1937 San Diego, CA (858) 768-0454 La Jolla, CA
If the aid determines that a sound is noise-like, that sound will be reduced while the speech-like signals are amplified. This is very helpful for patients having difficulty in background noise; however, it is not so sophisticated that it can determine a speaker of interest from a background of other voices. These are just a few of the many modern features of today’s digital instruments. However, this small sample demonstrates the leaps and bounds of the hearing instrument industry in today’s technological world. Ask your hearing healthcare provider to discuss these features and your options for hearing aids today! Call us today or visit our website or watch our videos on YouTube.
Peninsula Hearing Center (619) 569-1937 San Diego, CA (858) 768-0454 La Jolla, CA