Play stereo tone in android

Question

Similar topics on this question include only playing tone in mono where the left and right frequencies are the same.

My question is: how to generate a stereo tone such that the left channel has a different frequency than the right channel?

I thought of pre-recording .wav files but recording many .wav files and putting it on res folder is not a good idea.

i come across the SoundPool and AudioTrack class but I need a snippet showing the different frequencies of the left and right channel stored as buffer before playing the tone.

Or is there other ways? Please provide the desired snippet.

Answer 1

I have never tried this:

1. Initialize your left and right frequencies
   //playback rate (1.0 = normal playback, range 0.5 to 2.0)
float lFrequency = 1.0;
float rFrequency = 1.0;

2. Initialize a SoundPool object
   SoundPool sp = SoundPool(2, AudioManager.STREAM_MUSIC, 0);

3. Load your track twice (load function)
   int sLeft = sp.load(mContext, R.raw.yourAudioFileId, 1);
int sRight = sp.load(mContext, R.raw.yourAudioFileId, 1);

4. Play the 2 sounds (one on Left and one on Right) using different rates (play function)
   sp.play (sLeft, 1.0, 0.0, 0, 0, lFrequency);
sp.play (sRight, 0.0, 1.0, 0, 0, rFrequency);

Answer 2

From my understanding, if you use SoundPool it will play in stereo without any special configuration. From the documentation: "The SoundPool library uses the MediaPlayer service to decode the audio into a raw 16-bit PCM mono or stereo stream" so as long as the file you play is in Stereo to begin with, it should play that way.