In the last post about the Media Enhanced Learning Special Interest Group (MEL SIG) I recorded a short audio interview with Carol Beattie using Skype, the free software app that lets make voice calls over the internet . So I thought I’d write up the process of recording a Skype conversation using software.
Recording Skype conversations make a great basis for creating podcasts. For example, interviewing subject experts or recording conversations with peers at different locations. My colleague, Martin does this in partnership with Kevin Brace, formerly of JISC RSC West Midlands. Their monthly podcasts using Skype are an excellent example of how useful this technology can be. Martin’s in Edinburgh and Kevin’s based in the West Midlands. You can listen to their podcasts here.
If you’re familiar with Audacity, the open source audio editor, you may be tempted to use the stereo mix facility to record your Skype conversations. Unfortunately, that won’t work because Skype uses your soundcard’s playback channel so that you hear what the remote host is saying AND it also uses the recording channel to transmit what you are saying. Therefore, Audacity will only record your side of the conversation. Fortunately, there are lots of tools out there that let you record Skype conversations. If your on a Mac, there is Audio Hijack Pro and Call Recorder. On the PC there’s CallBurner, HotRecorder and the oddly named Pamela. That’s just a snapshot. There are many more alternatives.
So for the recording I did with Carol Beattie about MELSIG, I used Skype and CallBurner. It’s quite a wordy process to describe – much quicker to do than to write up so I’ll start with a process summary.
Process Summary
1. In CallBurner, go to Options > Configure > Recording window check the Store raw audio box
2. Import This Side.wav and Other Side.wav into Audacity for editing
3. Run your new .Wav file through The Levelator to optimise audio
4. Create an MP3 file with ID3 tags for putting online
Process
1. After you’ve installed CallBurner go to the Options menu and click on Configure…
We have two tabs here: General and Recording. Under the General tab I tend to leave Start CallBurner when I start Windows unchecked as I don’t record skype calls on a regular basis. One less thing to hog my memory. These are personal preferences though so its up to you!
Next is the Recording tab. We have various options here. In the Audio Format section you can record directly to MP3 or a number of other formats by clicking on the Change… button.
Regardless of audio format, this will produce a single file. This may be handy if you want to quickly put a file online without any further editing or if it’s just for personal use.
However, one of the handiest features of CallBurner, and for me the most useful is the ability to record both sides of the conversation into separate uncompressed files. Just check the Store raw audio option.
When you record a Skype conversation, CallBurner creates a date-stamped folder with a single combined MP3 file containing your audio conversation (if that’s the audio format you’ve chosen) and if you’ve chosen to store the raw audio it will create two further files: This Side.wav, your audio and the Other Side.wav, the remote caller’s audio. This allows you to do individual editing of tracks, where you can for example adjust levels, remove ums and ahhs etc and you have the benefit of working with the raw, uncompressed .Wav files. It’s always a good idea to work with raw files when editing as they contain more audio information.
2. Now that we have the two raw audio files the next step is to import them into Audacity to do a bit of editing. Open Audacity and go to the Project menu and choose Import Audio… then open Other Side.wav and This side.wav.
Now we need to make the track stereo while we edit the tracks so that the audio tracks stay in sync. To do that click on the drop down arrow next to the name of either track and choose Make Stereo Track
We can now edit the file as necessary. If you want to know more about editing Audacity they have a tutorial page on their website. You may also want to include an audio ident. This is usually a short piece of audio at the beginning and end of your audio file. This creates an identity or branding for your audio. When listeners here it they immediately identify it with your audio. It’s used extensively in Radio. If for example you hear the intro music to Desert Island Discs you probably immediately associate it to that programme and know that you are listening to Radio 4.
When you’ve finished editing your audio the next step is to make the tracks mono again. This tends to be a lot easier to listen too than having one speaker in the left ear and the other in your right ear. To do this go back up to the dropdown menu beside either of the tracks name and choose Split Stereo Track.
And then for both tracks click on the drop-down menu and choose Mono
Now go to the File menu and choose Export as WAVE… and save your new file.
3. A handy little tool I’ve used since it came out in 2005 is The Levelator. The screenshot below from wikipedia shows an example of what it does. On the top stereo track you’ll see that the volume level varies – it gets louder and quieter (the amplitude of the wave). Once you run it through The Levelator it levels out and optimises your audio file shown in the bottom track.
The Levelator has a very simply interface. Just open it up and drag your .Wav file on top of it. It will then optimise your audio. This will create a new file and append output onto the title. In this example the new file will be called melsig.output.wav. There are no user adjustable attributes in The Levelator, just drag and drop and it creates your new file.
4. Final Step (honest!). The most common audio file format on the web is MP3. This compressed format offers a good balance between sound quality and file size. So we need to convert our newly optimised .Wav file to MP3 format. If you’ve got the lame encoder installed for Audacity then you can do it there but I prefer to use iTunes, the free media player from Apple, to convert my MP3 files. For me, it has a better interface and has the bonus of allowing you to embed an image to your file so that it can be displayed on your mobile device (if it supports that function) or on your computer.
Fire up iTunes, Go to the Edit menu and choose Preferences. Under the General tab click on Import Settings. Set the Import Using: to MP3 Encoder and the Setting to Good Quality (128 kbps) which is more than fine for spoken audio.
Now go to the File menu and choose Add file to library… and locate the .Wav file you want to convert. Add it, then locate it in your library. Right-click on the file and choose Create MP3 Version
This creates your new MP3 file. Locate that in iTunes then right-click on the file and choose Get Info. As you’ll see in the screenshot below we now have a mono MP3 file.
Next, is to fill in the ID3 information under the Info tab. This is the info that’s displayed on your MP3 player.
The final thing to do is to add your image. This could be your institutional logo or something you’ve designed yourself to identify your audio. Possibly not your Simpsons avatar which was the only image I had to hand at the time :-) Click Add… then locate and add your image file.
That’s it! Phew :-) Your new MP3 is ready to be uploaded to your blog or where ever you’re sharing it. In Part 2, I’ll be looking at the more fun (for me), geeky way to record Skype using a mixer and audio recorder.
3. Click on the rectangle with the outward pointing arrows to make the map full screen
