Every electrical hearing aid has three parts; a microphone, an amplifier and a receiver.
The Microphone - This collects the sound and converts it into electrical impulses. These reproduce the rise and fall of pitch of the sound (high or low) and the intensity (loudness measured in decibels).

The Amplifier - This modulates the electrical impulses, makes sounds louder or quieter. It can have an integrated circuit with up to 30 transistors or a combination of circuits. The digital aid uses the efficient micro-chip.
The Receiver - It converts the amplified signal into sounds and feeds them into the ear.
Hearing aids get their power from tiny batteries.

Hearing Aid Technology can be divided into two different categories:
Analog Hearing Aids - This conventional technology amplifies all sounds equally. Your Audiologist sets the amplification level, though it can be adjusted later. Loud sounds may require you to manually turn down the volume on your hearing aid. This type of technology is best for people who do their communicating in relatively quiet situations. Basic analog is the least expensive technology. Analog hearing aids are slowly being phased out. Some companies make only digital hearing aids.
Digital Hearing Aids - With this type of technology, a computer chip converts incoming sound into digital code, then analyze and adjusts the sound based on your hearing loss and listening needs. The signals are then converted back into sound waves and delivered to your ears. The result is sound that's more finely tuned to your hearing loss. Digital hearing aids are available in all styles and the price you pay will depend on the features you choose. More advanced digital signal processing capabilities tend to translate into higher cost. If price is a concern, let your Audiologist know and choose the best combination of features in your price range.

Hearing Aid Accessories
Directional Microphones - Helps you focus on sounds coming in front of you by reducing sounds coming from the side and behind you. This technology improves your ability to hearing when you're in an environment with a lot of background noise. The latest directional microphone systems automatically adapt and reduce multiple noise sources around you. This system now includes the use of three microphones.
Telephone adapters - This technology, also referred to as telecoils, makes it easier to hear when talking on the telephone. Flipping a switch directs your hearing aid to eliminate sounds from the environment and pick up sounds from the telephone only. Keep in mind this feature only works with telephones that are hearing aid compatible.
Speech and Noise Management - This technology allows for special listening programs to be set that offer personalized sound processing for specific listening needs such as listening to music.
Feedback Cancellation - Continually analyzes incoming signals and adjusts seamlessly and instantaneously to minimize feedback (whistling) Also, maintains excellent sound quality
Multiple Listening Programs - Adjusts the way sound is processed to adapt to specific listening situations including listening on the telephone or to music.
Wireless Technology - Highly advanced instruments use wireless technology to literally communicate with each other when wearing two hearing instruments (binaural amplification). Sound processing is synchronized for optimized sound quality. Wearers can use one control to operate both instruments No hearing aid can solve every hearing problem or restore normal hearing, but they are designed to provide amplification so that you can hear and understand better.