Hearing Aid Technology Glossary
Comprehensive dictionary of hearing aid terms, technologies, and features
Core Technology(4 terms)
Digital Signal Processing (DSP)
The computer chip technology that converts sound waves into digital signals, processes them according to the user's hearing loss profile, and converts them back to audible sound. All modern hearing aids use DSP for superior sound quality compared to analog amplification.
Channels
Independent frequency bands in a hearing aid that can be adjusted separately. More channels (typically 12-48 in premium aids) allow for more precise fitting to your specific hearing loss pattern. Entry-level aids may have 6-8 channels, while premium aids have 20+ channels.
Gain
The amount of amplification a hearing aid provides, measured in decibels (dB). Different gain is applied at different frequencies based on your audiogram. Maximum gain ranges from 30dB in mild loss aids to 80dB+ in power aids for severe loss.
Compression
A processing method that automatically reduces loud sounds while amplifying soft sounds, keeping all sounds within a comfortable listening range. Types include WDRC (Wide Dynamic Range Compression), AGC (Automatic Gain Control), and peak clipping.
Connectivity(6 terms)
Bluetooth
Wireless technology allowing hearing aids to connect directly to smartphones, TVs, and other devices. Bluetooth Low Energy (BLE) is most common, enabling audio streaming and app control. Made for iPhone (MFi) and ASHA (Android) are specific protocols.
Made for iPhone (MFi)
Apple's proprietary protocol allowing hearing aids to stream audio directly from iPhones, iPads, and Macs without an intermediary device. Provides lower latency and better battery efficiency than classic Bluetooth. ReSound pioneered MFi hearing aids in 2014.
ASHA (Audio Streaming for Hearing Aids)
Google's protocol enabling direct audio streaming from Android devices to hearing aids. Available on Android 10+ devices. Not all Android phones support ASHA; check compatibility with specific hearing aid brands.
Telecoil (T-Coil)
A small copper coil inside hearing aids that picks up electromagnetic signals from hearing loop systems installed in theaters, churches, airports, and public venues. Also works with telecoil-compatible landline phones. Not available in smallest IIC models.
Hearing Loop (Induction Loop)
An assistive listening system that transmits audio directly to telecoil-equipped hearing aids via magnetic field. Common in public venues. Look for the international hearing loop symbol (ear with T) indicating loop availability.
Near-Field Magnetic Induction (NFMI)
Wireless technology enabling communication between two hearing aids (ear-to-ear) and with accessories like remote microphones and TV streamers. Uses less power than Bluetooth but has shorter range (about 1 meter).
Noise Management(5 terms)
Directional Microphones
Microphone systems that focus on sounds from specific directions (usually front) while reducing sounds from sides and behind. Types include fixed directional, adaptive directional, and binaural beamforming where both aids work together.
Beamforming
Advanced directional technology where multiple microphones work together to create a focused 'beam' of sensitivity toward the desired sound source. Binaural beamforming uses microphones from both hearing aids for superior directionality.
Digital Noise Reduction (DNR)
Algorithm that identifies and reduces steady-state background noise (fans, traffic, air conditioning) while preserving speech signals. More advanced systems can reduce modulated noise and even some speech babble.
Wind Noise Reduction
Specialized processing that detects and reduces wind turbulence noise hitting the hearing aid microphones. Essential for outdoor use. Some systems use additional microphone placement or acoustic barriers.
Feedback Cancellation
Technology that prevents or eliminates the whistling sound (feedback) that occurs when amplified sound leaks from the ear canal back to the microphone. Modern systems use phase cancellation and are highly effective.
AI & Automation(5 terms)
Artificial Intelligence (AI) in Hearing Aids
Machine learning algorithms that automatically classify listening environments, optimize settings in real-time, and learn user preferences. Examples include Starkey's Edge Mode, Signia's Integrated Xperience, and Phonak's AutoSense OS.
Deep Neural Network (DNN)
Advanced AI architecture trained on millions of sound samples to provide superior noise reduction and speech enhancement. Oticon pioneered DNN in hearing aids with the Velox S platform. Processes sound more like the human brain.
Automatic Environment Classification
Feature that detects the listening environment (quiet, speech, noise, music, car, outdoor) and automatically adjusts hearing aid settings. Premium aids detect 7+ environments; entry-level may have 3-4.
Own Voice Processing (OVP)
Signia's patented technology that processes the wearer's own voice separately from external sounds, making it sound more natural. Uses sensors and AI to detect when the wearer is speaking. Addresses the #1 complaint of new hearing aid users.
Edge Computing
AI processing performed directly on the hearing aid chip rather than streaming to a smartphone or cloud. Provides faster response times and works without phone connection. Starkey's Edge Mode+ is an example.
Sound Features(5 terms)
Frequency Lowering
Technology that moves high-frequency sounds (where hearing loss is often greatest) to lower frequencies where hearing may be better. Types include frequency compression, frequency transposition, and frequency composition.
Tinnitus Masking/Management
Built-in therapy sounds (white noise, ocean waves, chimes) that help mask tinnitus (ringing in ears). Widex Zen therapy uses fractal tones; Signia offers Notch therapy that targets specific tinnitus frequencies.
Music Program/Mode
Specialized processing settings optimized for music listening rather than speech. Typically disables or reduces noise reduction and compression to preserve musical dynamics and fidelity. Essential for musicians and music lovers.
Speech Enhancement
Processing that specifically boosts speech frequencies and clarity. May use directional microphones, noise reduction, and frequency-specific amplification. Critical for the primary goal of hearing aids: understanding speech.
Spatial Awareness/360° Sound
Processing that preserves natural spatial cues so users can locate sound sources and maintain awareness of their environment. ReSound's Organic Hearing and Oticon's OpenSound Navigator are examples.
Hearing Aid Types(6 terms)
BTE (Behind-the-Ear)
Hearing aid style where the main body sits behind the ear, connected to an earmold or dome in the ear canal. Most powerful style, suitable for all hearing losses. Largest size but easiest to handle. Battery life is longest.
RIC/RITE (Receiver-in-Canal)
Style where the main body is behind the ear but the speaker (receiver) sits inside the ear canal. Most popular style today, offering natural sound quality, discretion, and Bluetooth capability. Suitable for mild to severe loss.
ITE (In-the-Ear)
Custom-molded hearing aid that fills the outer ear (concha). Larger than canal styles, allowing for more features including volume controls, directional mics, and larger batteries. Suitable for mild to severe loss.
ITC (In-the-Canal)
Custom hearing aid smaller than ITE, sitting in the lower portion of the outer ear. Balances discretion with features. May include directional microphones. Suitable for mild to moderately severe hearing loss.
CIC (Completely-in-Canal)
Small custom hearing aid that fits entirely within the ear canal, with only a small removal handle visible. Nearly invisible but limited in features (usually no Bluetooth, directional mics, or telecoil). For mild to moderate loss.
IIC (Invisible-in-Canal)
Smallest hearing aid type, placed deep in the ear canal making it completely invisible. Removed daily. Limited features and battery life. Requires adequate ear canal size. For mild to moderate hearing loss only.
Battery & Power(3 terms)
Lithium-Ion Rechargeable
Built-in rechargeable battery lasting 20-30 hours per charge (less with heavy streaming). Charges in 3-4 hours; some offer quick charge (30 min for 6 hours). Most convenient option, eliminating tiny battery changes.
Zinc-Air Battery
Disposable hearing aid batteries activated by exposure to air (remove tab and wait 1 minute before insertion). Sizes: 10 (yellow, 3-5 days), 312 (brown, 5-7 days), 13 (orange, 10-14 days), 675 (blue, 2-3 weeks).
Silver-Zinc Rechargeable
Rechargeable battery type used by some manufacturers (ZPower system). Can be swapped for disposable zinc-air batteries if needed. Being phased out in favor of lithium-ion in most brands.
Fitting & Customization(5 terms)
Audiogram
Graph showing your hearing thresholds (quietest sounds you can hear) at different frequencies (pitches). The foundation for programming hearing aids. X-axis shows frequency (250-8000 Hz), Y-axis shows intensity (0-120 dB).
Real Ear Measurement (REM)
Gold standard verification method using a probe microphone in the ear canal to measure actual sound levels delivered by the hearing aid. Ensures prescription targets are met. Not all fitters use REM; ask for it.
First Fit
Initial automatic programming of hearing aids based on audiogram using manufacturer's fitting formula. Starting point that should be fine-tuned based on user feedback and real ear measurements.
Acclimatization
The adjustment period (typically 30-90 days) when a new hearing aid user adapts to amplified sound. Initial settings may be reduced and gradually increased. Brain needs time to relearn how to process sound.
Occlusion Effect
The 'plugged up' or boomy sound of your own voice caused by blocking the ear canal. Reduced by open fit domes, vents, or own voice processing technology. Major reason some users reject hearing aids.
Health Features(3 terms)
Fall Detection
Sensors in hearing aids that detect falls and can automatically alert designated contacts. Starkey is the only major brand currently offering this feature in their Genesis AI and Livio AI lines.
Activity Tracking
Hearing aids that count steps and track physical activity using built-in motion sensors. Data viewable in smartphone app. Primarily offered by Starkey; some other brands track 'brain engagement' via listening activity.
Cognitive Health Tracking
Features that monitor and encourage hearing aid usage to support brain health. Research links untreated hearing loss to accelerated cognitive decline. Some apps track 'brain score' based on listening engagement.
Service & Support(3 terms)
Remote Fitting/Teleaudiology
Hearing aid adjustments made remotely by an audiologist via smartphone app, without in-person visit. Available from most major brands: Signia TeleCare, Phonak Remote Support, ReSound Assist, Starkey Hearing Care Anywhere.
Data Logging
Hearing aids automatically recording usage data: hours worn, listening environments encountered, volume adjustments made, programs used. Helps audiologists optimize settings based on actual use patterns.
IP Rating (Ingress Protection)
Standard rating for dust and water resistance. IP68 is best (dust-tight, submersible). IP67 is dust-tight, splash-resistant. Most premium RIC/BTE hearing aids are IP68 rated. Custom aids typically have lower ratings.
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Last updated: 21 June 2026
Content reviewed by HearClear's team of RCI-certified audiologists