How does stereo recording work?

Stereo recording is a bit tricky. Many phones with a single microphone report that they can record in stereo. Conversely, many phones that has multiple mics refuse to record in stereo.

First, it seems that Android will just accept our app’s request to record in stereo, although actually there is only one mic. It will duplicate the audio signal exactly, so the left and right channels contain the same data. The resulting MP3 file will still be in stereo, but with exact same waveform for both channels.

Second, some devices have multiple mics but they are not for stereo recording purposes. They are there to assist in noise cancellation. Using two microphones they can compare the differences of the audio signal between the mics, and extract only the difference as the audio signal given to apps.

On some phone models, it is possible to actually record in stereo if you change the mic used for recording. Go to Hi-Q MP3 Voice Recorder settings, and change the Mic selection option. Try changing it to the “rear microphone” or the others.

Starting from version 1.20.2, we will automatically analyze the audio signal when you enable stereo mode from the settings. You will get a notice if we determine that the stereo recording does not actually work on your device (duplicated audio signal as above). Please let us know if your device supports stereo, and we will add it to the list!

Devices known to be able to record in stereo. Note that if your device is not on the list, it does not mean that your device does not support it. Many new devices support stereo recording.

  • Oneplus 5
  • Samsung Galaxy Note II
  • Samsung Galaxy S7 (with Rear microphone)
  • Samsung Galaxy S5
  • Samsung Galaxy S4
  • Samsung Galaxy A5 (with Rear microphone)
  • Redmi Note 4 (with Rear mic or Raw audio)

Devices known to duplicate audio signals (stereo does not work)

  • Samsung Galaxy Nexus
  • Most low-end Android smartphones