1. Box-type hearing aids, also known as pocket-type or miniature hearing aids, are slightly larger than a matchbox. The main unit and earpiece are connected by a wire. When in use, the earpiece is inserted into the ear canal, and the box is placed in a front pocket. Their advantages include less interference, higher power, ease of use, easy adjustment, long lifespan, and lower price, meeting the needs of people with severe hearing loss. However, these hearing aid boxes produce a rubbing sound when placed in a pocket, affecting speech recognition, and are quite noticeable when worn, sometimes causing inconvenience.
2. Behind-the-ear (BTE) hearing aids are 3-4 cm long and hook-shaped, placed behind the auricle. Sound is delivered into the ear canal through a ram's horn-shaped hook and a plastic tube. Their advantages include no wires, small size, discreetness, less interference, and the ability to add an induction coil for telephone use. Disadvantages include the need for a specially made earmold, initial unfamiliarity, and inconvenience in adjustment.
3. In-the-ear (ITE) and in-the-canal (ITC) hearing aids are small hearing aids with advantages such as being tiny, discreet, wire-free, requiring no additional earmold, providing good sound quality, and improving hearing. However, they are inconvenient to adjust, expensive, and require customization to fit each individual's ear canal and concha. Due to their lower power, they are only suitable for moderate hearing loss and not for severe or profound hearing loss.
When selecting a hearing aid, it is best to go to a hospital for a comprehensive hearing test. Using instruments such as audiometry, the degree of hearing loss can be accurately evaluated before selecting a hearing aid. If there is no hospital with the necessary facilities in your area, the degree of hearing loss and the appropriate hearing aid power can be estimated using a speech test.
