Sound Amplifier: Hearing Boost

Sound Amplifier is a hearing amplifier for your earphones. Your phone's microphone picks up the room around you and you hear it louder and clearer, live. Use it to follow dinner-table conversation, catch TV dialogue without blasting the volume, or hear a speaker from the back row.

Missed a sentence? Tap "Replay last 10s". Want the sound matched to your own ears? Take the Hearing Test and turn the result into a Personal EQ.

FEATURES
• Live boost from 0 to +40 dB, with a level meter that moves as sound comes in
• "Replay last 10s" plays back the past 10 seconds; that audio is held in memory only and cleared when you stop amplifying
• Voice leveler evens out loud and quiet voices, adding up to +12 dB to soft talkers
• Noise reduction trims low rumble (roughly 100 Hz and below) from fans, air conditioning, traffic and wind
• 3-band EQ for bass, mid and treble, ±12 dB each
• Presets: Speech, Music, Outdoor and Flat, plus Personal from your hearing test
• Left/right balance for when one ear needs more

HEARING TEST
• Tones at 250, 500, 1000, 2000, 4000 and 6000 Hz, left and right ear separately
• Earphones or headphones are required for the test
• One tap turns your result into the Personal preset
• Your history keeps up to 24 results and compares each one with your first test; differences under 10 dB are shown as no change

MY SETUPS
Save up to 8 named setups, such as "TV", "Church" or "Lecture", and switch between them with one tap. Saving is unlocked by watching a short video.

SAFETY BUILT IN
• Safety limiter with a ceiling you choose between -18 and 0 dBFS
• The app will not amplify through the phone's own speaker, because the mic would pick that sound up again and howl
• If your earphones disconnect, amplifying stops and a card tells you why; plug back in and tap "Resume"

WHERE IT HELPS
• TV and movies at a volume that suits the rest of the family
• Restaurants, coffee shops and family get-togethers
• Lectures, meetings, sermons and guided tours
• Birdsong and quiet nature sounds on a walk

HOW TO USE
1. Connect wired or Bluetooth earphones
2. Tap "Start Amplifying"
3. Raise the boost slowly until voices sound comfortable
4. Pick a preset, or run the Hearing Test for a Personal EQ
5. Save the setup for next time

FAQ
Wired or Bluetooth? Both work. Wired earphones give the lowest delay; Bluetooth adds some lag.
Why not the phone speaker? Speaker output feeds back into the microphone and squeals, so the app needs earphones.
Does noise reduction silence everything? No. It cuts low rumble; voices and higher sounds still come through.

Sound Amplifier is not a medical hearing aid and does not diagnose hearing loss. If you are concerned about your hearing, please see a hearing professional.

Recent changes:
When amplifying doesn't produce sound on the first try, the app now retries once automatically, and the message offers “Try again” rather than telling you to reopen the app. The Listen tab also explains up front that wired or Bluetooth earphones are needed — amplifying is blocked when the phone's speaker is detected as the output, to prevent feedback whistling.