Speaker & Stereo Test
Check left and right channels, try a range of test tones, and make sure your speaker plays clearly.
How to use
- 1Turn your volume up and switch off Silent mode on iPhone.
- 2Tap Left, Right or Both to check each channel.
- 3Try the frequency tones from low to high.
- 4Use the volume slider to check for rattling at higher levels.
How the stereo test works
Many phones play stereo using the bottom speaker and the earpiece speaker together. The Left and Right buttons send the tone to one channel only. Turn your phone sideways to hear which side the sound comes from. On headphones the separation is obvious; on a phone it's subtler but still noticeable.
If you hear both channels from one side only, your phone may be mono, a speaker may be weak, or an accessibility setting such as Mono Audio may be on.
Reading the frequency tones
Small phone speakers can't reproduce deep bass well, so the 100 Hz tone may sound quiet — that's normal. Mid tones around 440 Hz and 1,000 Hz should be clear and steady. High tones like 10,000 Hz may be hard to hear, especially as we get older; that's about your ears, not your phone.
Signs of a speaker problem
- Buzzing or rattling at medium volume.
- Crackling that changes when you press around the speaker.
- One channel much quieter than the other.
- Muffled sound after the phone got wet — try the speaker cleaner first.
Quick fixes to try
Remove the case, gently brush the grille, and restart the phone. Check Settings for Mono Audio and balance sliders under Accessibility. If the sound became muffled after contact with water, run the speaker cleaner and let the phone dry for a few hours.
Persistent rattling or distortion usually means a damaged speaker, which a repair shop can replace fairly cheaply on most models.
Helpful products
Affiliate links — we may earn a commission.
- Portable Bluetooth speaker
A louder, fuller sound when the phone speaker isn't enough.
- Phone repair service
Speaker replacements are a common, affordable repair.
Frequently asked questions
Why don't I hear any sound?
On iPhone, Silent mode mutes browser audio. Also check volume and Bluetooth connections.
Does my phone have stereo speakers?
Many recent phones do, using the earpiece as a second speaker. Older and budget phones are often mono.
Why can't I hear the 10 kHz tone?
High-frequency hearing declines naturally with age, and some phone speakers roll off at high frequencies.
Is a weak 100 Hz tone a fault?
Usually not. Small phone speakers physically can't move enough air for strong bass.
Can I test headphones with this?
Yes. Connect them and use Left and Right to confirm the channels are the right way round.
What is Mono Audio?
An accessibility setting that sends the same sound to both channels. If it's on, Left and Right will sound identical.
Related guides
Related tools
Speaker Cleaner (Water Eject)
Play low tones that help push small water droplets out of your speaker grille.
Tone Generator
Generate any frequency from 20 Hz to 20,000 Hz with sine, square, sawtooth or triangle waves.
Microphone Test
Check your mic with a live waveform, level meter and 5-second recording.