How to create a huge wav file containing multiple tracks?

I recorded five audio tracks (48kHz, 32bit, 1h) which I would like to write into one file with 5 channels à (48kHz, 32bit, 1h). When I simply read the tracks with audioread , I run out of memory. Using system objects didn't help as it turned out that dsp.AudioFileWriter does not allow to write more than two channels at once. Is there another technique how I could achieve that?

[Roman]

In version R2013b dsp.AudioFileWriter can handle more than 2 channels. However, if I copy one channel with the system object approach as shown below,

hafw = dsp.AudioFileWriter(RecFile,'FileFormat','WAV','SampleRate',hafr0.SampleRate);
hafr0 = dsp.AudioFileReader(PlayFile0,'SamplesPerFrame',SamplesPerFrame);
playbuff = zeros(SamplesPerFrame,5);
while ~isDone(hafr0)
    playbuff(:,1) = step(hafr0);
    step(hafw,playbuff);     
end

I get the following error after some time:

Error using AudioFileReader/step the audio input stream has become unresponsive.

Error in combine (line 31) playbuff(:,1) = step(hafr0);

Any idea what could have gone wrong?

Answer 1

[Roman]

I couldn't solve the problem right in Matlab but with "SoX, the Swiss Army knife of sound processing programs" I was able to merge the tracks.

http://sox.sourceforge.net/