Amplification systems: Hearing aids. May be analog or digital Consists of a microphone, amplifier, and loudspeaker. Earlier: Linear. Now, compressive with automatic gain control Directional microphones
May be analog or digital
Consists of a microphone, amplifier, and loudspeaker.
Earlier: Linear. Now, compressive with automatic gain control
Different types of hearing aids: Body level, BTE, ITE, ITC, CIC, Bone-conduction, Eyeglass, disposable, CROS.
Middle ear implants
Auditory brainstem implants
Direct stimulation of the auditory nerve
Candidacy issues: Age, hearing loss
Candidacy: Should depend on individual’s specific needs.
Goal of amplification: To restore sensitivity, clarity (in quiet and noise) and to prevent amplification to intolerable levels.
Earlier: Comparative methods
Now: Prescriptive methods
Verification of hearing aid performance very important. Compensate for insertion loss. Real ear measures.
Allows the signal to be closer to the amplification system.
Interface can be FM, infrared, or electromagnetic coupling .
Other types: For awareness. Example: Visual or vibrotactile devices.