NAudio ASIO mixing

Question

I'm trying to make a very simple DAW in C# with NAudio and winforms. The goal of the program at this stage is to be able to record from a microphone while playing back a couple of audio files. The project so far is a combination of the ASIO-samples that came with NAudio and information on the Internet.

I have one audiofilereader-object for each audiofile I want to play:

reader = new AudioFileReader("Audio 8_01.wav");

reader2 = new AudioFileReader("Audio 9_04.wav");
reader3 = new AudioFileReader("Click.L.wav");
reader4 = new AudioFileReader("Click.R.wav");

When pressing the play-button the audio-clips should start playing and recording should start on channel 1:

private void Play()
    {
        // allow change device
        if (asioOut != null &&
            (asioOut.DriverName != GetDriverOutComboBoxText() ||
            asioOut.ChannelOffset != 0))
        {
            asioOut.Dispose();
            asioOut = null;
        }

        int recordChannelCount = 0;


        mix = new MixingWaveProvider32();

        //Console.WriteLine("CHannels: " + mix.WaveFormat.Channels );
        mix.AddInputStream(reader);
        mix.AddInputStream(reader2);
        mix.AddInputStream(reader3);
        mix.AddInputStream(reader4);
        Console.WriteLine("CHannels: " + mix.WaveFormat.Channels);

         if (asioOut == null)
        {
            asioOut = new AsioOut(GetDriverOutComboBoxText());
            recordChannelCount = 1;
            asioOut.ChannelOffset = 0;
            asioOut.InitRecordAndPlayback(mix , recordChannelCount, 96000);
            asioOut.AudioAvailable += OnAsioOutAudioAvailable;

        }

        outFileName = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".wav");
        Console.WriteLine("File: " + outFileName);
        writer = new WaveFileWriter(outFileName, new WaveFormat(96000, recordChannelCount));

        reader.Position = 0;
        asioOut.Play();
        timer1.Enabled = true;
        //SetButtonStates();
    }

I use a mixingwaveprovider to be able to play multiple files at the same time. It works somewhat, if the audiofiles in the readers are stereo audio I get sound in both speakers and the mix.WaveFormat.Channels is 2 before and after adding the file-readers to the mixer. If the files are mono-audio they all get played in either left or right speaker depending on the asioOut.ChannelOffset being set to zero or one. I don't know how to set to which channel each audiofile is played, and I want to be able to adjust panning, ie. a mono-sound being played in both speakers to some degrees. I feel there is something that I'm missing...I have seen the Patchbay-example program that Mark Heath has written but I don't really know how to apply that to my project. All audio files are in the same format by the way.

The other problem that might be related, otherwise I'll post a new question, is that the audio being recorded(which works fine by the way) is not audible in the speakers during recording, ie. no monitoring during recording. How can I send this signal being recorded to the same mixer as the files are being sent to?

Thanks!

Ano Ano · Accepted Answer · 2017-09-05T15:32:24

This might be a late answer, but when I have to pan audio, I use the WaveChannel32 Class in NAudio. This is a simple VB.NET example:

  Dim mixer As New MixingWaveProvider32()
  Dim audioreader As New AudioFileReader("SourceFile.mp3")
  Dim wav32 As New WaveChannel32(audioreader)

  wav32.Pan = -0.5

  mixer.AddInputStream(wav32)

NAudio ASIO mixing

1 Answers