Speaker test — left and right, stereo and frequency sweep
Speaker test
Press Start to play left, right, both, bass and a full sweep — 25 seconds in total. Use Custom tone to hold any single frequency.
Hold the phone sideways at arm’s length and listen to each end.
Using headphones? Turn the volume down before you start.
Test finished. Left and right tones from different ends mean both speakers work. A buzz or rattle during the sweep points to debris, water or damage.
Tone finished.
A speaker test plays known sounds so you can hear whether each speaker works and where it distorts. This one plays the left channel, the right channel, both together, a 60 Hz bass tone and a sweep from 20 Hz to 20 kHz — 25 seconds on phones, laptops, Bluetooth speakers or headphones.
The sections below explain the left and right check, what a stereo test tells you, how to read the result on a phone, and how to use the sweep to find a rattle.
Left and right speaker test
A left and right speaker test plays a 440 Hz tone on one channel at a time for 2.5 seconds each, then on both. If the first tone comes from the left and the second from the right, the two channels are wired and working the right way round.
On a phone with stereo sound, turn it sideways and hold it at arm’s length, because the two outputs sit at opposite ends of the phone. On headphones, check the L and R marks before blaming the test; for a quieter left or right AirPod, Apple’s balance and cleaning steps come first. A channel that seems silent is often a setting: on iPhone, Settings, then Accessibility, then Audio & Visual holds Mono Audio and the Balance slider, and Mono Audio makes both sides play the same content.
Stereo test
A stereo test checks that left and right carry different sound and that they stay in balance. The “Both speakers” step matters here: the tone should seem to come from the middle, between the speakers or inside your head on headphones.
| What you hear | Likely cause | What to do |
|---|---|---|
| Left and right tones come from opposite sides | Both channels work | Nothing — move on to bass and sweep |
| Both tones come from the same place | Mono Audio on, a single-speaker device, or a mono Bluetooth speaker | Check the audio accessibility settings; mono hardware is normal |
| One tone is much quieter | Balance slider off-centre, or one speaker blocked | Centre the balance, then run the speaker cleaner |
| One tone is silent | A dead channel, a loose headphone plug or a Bluetooth issue | Reconnect, try other headphones, then consider a repair |
| “Both” sounds off to one side | Uneven output or a partly blocked grille | Clean the quieter side and test again |
Phone speaker test
A phone speaker test works the same on iPhone and Android, with one limit: a web page reaches the speakers that play music and video, not the earpiece used for calls. For a muffled call speaker, see the call speaker cleaner.
Step 1
Disconnect Bluetooth
Otherwise the test plays on your earbuds or car stereo, not the phone.
Step 2
Turn off Silent mode
On iPhone, use the Ring/Silent switch or the Action button, then turn the volume up.
Step 3
Hold it sideways
Keep the phone at arm’s length so you can tell which end each tone comes from.
Step 4
Press Start
Listen to left, right and both, then the bass tone and the sweep.
Step 5
Compare with the table
A quiet or rattling side after water or dust is a cleaning job before it is a repair.
On iPhone, Apple’s own check is in Settings, then Sounds & Haptics: drag the Ringtone and Alerts slider back and forth. If you hear nothing, or the speaker button on that slider is dimmed, Apple says the speaker might need service. The iPhone speaker troubleshooting guide walks through the rest of Apple’s steps.
Test my speaker with a frequency sweep
A frequency sweep tests a speaker by gliding from 20 Hz to 20 kHz over 14 seconds, so every pitch plays in turn. A healthy speaker gets louder and quieter smoothly. A buzz, rattle or sudden dropout at one point marks a frequency where something vibrates that shouldn’t.
Two things are normal and not faults. Small speakers, especially on phones, are nearly silent at the very start of the sweep, because deep bass needs a larger speaker to move enough air. And if the top of the sweep fades out, play it through headphones you trust: if they fade at the same point, the limit is your hearing or the audio chain, not the speaker.
To study one frequency, switch to Custom tone and type the value where the rattle appeared. The sweep plays at a lower level than the other steps, but keep headphone volume moderate — the US National Institute on Deafness and Other Communication Disorders lists headphones and earbuds at high volume among sources of damaging noise. If the rattle came after water, the water eject tone is the next step. On Android, the phone vibration test checks the other moving part a phone relies on.