Concatenating audio blobs

The best way is to convert the blobs into AudioBuffers (Convert blob into ArrayBuffer using FileReader and then decode those arrayBuffers into AudioBuffers). You can then merge/combine more than one AudioBuffers and get the resultant. Following code will work in such situation:

var blob="YOUR AUDIO BLOB"; var f = new FileReader(); f.onload = function (e) { audioContext.decodeAudioData(e.target.result, function (buffer) { arrayBuffer.push(buffer); if (arrayBuffer.length > 1) { resultantbuffer = appendBuffer(arrayBuffer[0], arrayBuffer[1]); arrayBuffer = []; arrayBuffer.push(resultantbuffer); } else { resultantbuffer = buffer; } }, function (e) { console.warn(e); }); }; f.readAsArrayBuffer(blob); 

This code read the blob and convert into arrayBuffer (e.target.result) and decode those buffers into AudioBuffers (buffer). I used appendBuffer method for appending more than one audioBuffers. Here is the method:

function appendBuffer(buffer1, buffer2) { ///Using AudioBuffer var numberOfChannels = Math.min(buffer1.numberOfChannels, buffer2.numberOfChannels); var tmp = recordingAudioContext.createBuffer(numberOfChannels, (buffer1.length + buffer2.length), buffer1.sampleRate); for (var i = 0; i < numberOfChannels; i++) { var channel = tmp.getChannelData(i); channel.set(buffer1.getChannelData(i), 0); channel.set(buffer2.getChannelData(i), buffer1.length); } return tmp; } 

Do let me know if you face any problem.