private AudioRecord getAudioRecord() {
        final int SAMPLE_RATE = 16000;
        final int WAVE_FRAM_SIZE = 20 * 2 * 16000 / 1000; //20ms audio for 16k/16bit/mono
        try {
            int bufferSize = AudioRecord.getMinBufferSize(16000, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT);
//            AudioRecord recorder = new AudioRecord(MediaRecorder.AudioSource.DEFAULT, 16000, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, bufferSize);

            AudioRecord recorder = new AudioRecord(MediaRecorder.AudioSource.DEFAULT, SAMPLE_RATE,
                    AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, WAVE_FRAM_SIZE * 4);

            if (recorder.getState() == AudioRecord.STATE_INITIALIZED) {
                return recorder;
            }
        } catch (Exception e) {
            Log.e(TAG, "Error in Audio Record");
        }
        return null;
    }		
		
			

当设备中有多个麦克风时，我们希望切换到另一个麦克风，可以采用此方法。

		
AudioRecord audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, 16000, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, 16000 * 4);

        AudioManager audioManager = (AudioManager) MainApplication.getContext().getSystemService(Context.AUDIO_SERVICE);
        AudioDeviceInfo[] audioDeviceInfos = new AudioDeviceInfo[]{};
        audioDeviceInfos = audioManager.getDevices(AudioManager.GET_DEVICES_INPUTS);
        for (AudioDeviceInfo device : audioDeviceInfos) {
            if (device.getType() == AudioDeviceInfo.TYPE_USB_DEVICE && device.getProductName().equals("USB-Audio - USB PnP Sound Device")) {
                audioRecord.setPreferredDevice(device);
                Log.d(TAG, "Set microphone: " + device.getProductName());
            }

            Log.d(TAG, device.getId() + " | " + device.getProductName() + " | " + device.getType());
        }
        audioRecord.startRecording();
        Log.d(TAG, "AudioRecord state: " + audioRecord.getState());

        if (audioRecord.getState() != AudioRecord.STATE_INITIALIZED) {
            Log.e(TAG, "audio recorder not init");
        } else {
            byte[] audioData = new byte[1024];
            for (int i = 0; i < 100; i++) {
                int ret = audioRecord.read(audioData, 0, 1024);
                Log.d(TAG, String.valueOf(audioData));
            }
        }