Phase Checker - How can I check my speakers are in phase?

With this handy app!

Did you know that if your speakers are out of phase the sound quality is affected massively - bass is reduced significantly and stereo imaging is lost.

So what is phase? The tl;dr version

Speakers are out of phase if the wires for one of your speakers are connected the wrong way around. When this happens the sound from one speaker cancels out the sound from the other so you get reduced bass and poor stereo imaging.

In other words....not good!

When could this happen?

If you had to connect your speakers with wire with bare ends pushed into a connector or post it's possible to inadvertently connect one speaker 'the wrong way around'. If this happens the speakers will be out of phase and unless you are an experienced audio engineer you might not notice.

So how does this app work?

First connect your iOS device to your sound system so it can play sound through your speakers. If you cannot set this up the app will not be able to work.

If possible place the iOS device evenly between the speakers. Phase cancellation will not occur so much close to the speakers so ensure the device is not too close. Ensure the volume is at a comfortable listening level and if possible ensure there is no background noise to interfere with the scan.

You can then run the app in automatic mode or manual mode. Manual mode allows you to run the test signal and flip the phase so you can listen yourself to ensure your sound system is setup correctly. Automatic mode will run a series of test signals through your sound system and use the microphone on the device to analyse the results and tell you if the speakers are in phase or out of phase.

PhaseChecker app iPhone screenshot


Available on the App Store now.

Phase Checker iOS app icon

Phase Checker

For iPhone, iPod Touch and iPad

Download on the app store