Podcaster's Portal: file formats

File formats used in Audacity

IN THIS ARTICLE:

3 main file formats used by Audacity
WAV - professional standard for working with sound
MP3 - proprietary format of compressed audio
Ogg Vorbis non-proprietary audio format developed by open source programmers

By Jonathan Halls

Fifteen years ago we recorded our audio on quarter inch tape. The technical issues back then were at what speed to record our material.

You see, the faster the speed, the better the quality. I remember we used to record broadcast speech at 7 ½ inches per second, and music at 15 inches per second (IPS).

Now with digital audio, the issues around quality generally relate to bit rate and compression. Podcasters’ Portal recommends you use Audacity to record your podcasts because it’s a very effective piece of editing software and won’t cost you a penny.

So our discussion of file formats is focused on the three main formats that Audacity supports. These formats are WAV, MP3 and Ogg Vorbis. These are all digital audio file formats.

WAV Files
WAV is an industry standard file format for saving sound. WAV files are uncompressed and if used properly produce very high quality audio.

The problem with a WAV file – and indeed any uncompressed file - is it takes up a lot of disc space.

When producing your audio, it is important to have good quality. Therefore, WAV files tend to be used when recording and editing material in production.

However, a WAV file is generally not going to be necessary for general playback conditions. Except, of course, if your listener is a hi fi buff.

MP3 Files
MP3 files are quite common these days with the popularity of MP3 players and iPods. MP3 is a compressed audio file format.

Unlike a WAV file, MP3 files won’t take up much space on your disc. Which is why MP3 is the ideal file format for podcasts. MP3 compresses the higher quality audio file.

For example, a four minute podcast saved as a WAV file might take up 40MB of space. However, it will take less than 4MB of space when compressed to MP3.

While the quality is not as good as a WAV file, the average person is unlikely to notice any difference.

Ogg Vorbis
Like MP3 files, ogg vorbis files are compressed. In fact they tend to save a little more space than MP3 files.

Ogg Vorbis files are not as popular as MP3 files because they are free from patents and licensing restrictions.

Being a non-proprietary file format, there is no company promoting it.

Choosing the appropriate format
Generally speaking, when you record, edit and produce your audio content, you should save your work as a WAV file. That will maintain the best possible quality and highest consistency.

However, when your work is complete, you have no more edits and you want to publish it, you should publish it as a compressed file. That’s either a MP3 or an Ogg Vorbis.