On the Air

The term podcast was first used in 2004. At the time, the idea of publishing contributions in the form of audio files was an exciting new development in the data revolution. Since then, modern social media tools have taken some of the shine away from the podcast format. But podcasts are currently experiencing a revival thanks to streaming services such as Spotify. It doesn't matter whether you believe this 14-year-old technology is hip or not: Podcasts offer a convenient way to distribute your keynotes and thoughts in an audible form. More convenient than written text, they establish a more direct connection between the sender and receiver.

It is easy to produce a high-quality podcast. On a Linux system, you will find almost all the necessary components with the Audacity audio editing tool [1].

Audacity is aimed at (semi-)professional users and is used by many musicians. This article describes how to record and optimize podcasts with Audacity.

The Right Hardware

You already own most of the hardware you need to record podcasts. It doesn't matter whether you are using a desktop PC or a laptop. Most likely, the computer has a 3.5mm jack for connecting an external microphone. Laptops usually also come with an internal microphone that you could also use to record podcasts.

The choice of a microphone is a good place to start your podcast journey. What the microphone does not deliver in audio quality, even the best program cannot conjure up through post-processing. The microphones built into laptops are usually located near the keyboard – and are thus in close proximity to noisy components such as the CPU fan. A podcast recorded with an internal mic will almost inevitably include background noise, limiting the intelligibility and thus annoying the listeners.

If you want to record podcasts, you should consider purchasing a microphone suitable for this purpose. Even a simple headset mic, like one you might use for a video conference call, delivers sufficient audio quality for a podcast and is often available for less than $30. You do not have to confine the choice to a mic for the jack socket; a USB microphone usually offers the same quality. By the way, many external webcams also have very good microphones – your webcam might already meet your requirements.

Uncomplicated Entry

Audacity is included with all current desktop distributions and can be easily installed using the package manager. On a KDE system, Audacity installs to the K menu under the Multimedia entry.

Audacity 2.2 is now available, but some distributions install the less-recent Audacity 2.1. I recommend version 2.2, which comes with a revamped interface and offers many bug fixes. Ubuntu packages are available from a dedicated Ubuntu PPA [2]. PackMan [3] offers openSUSE packages.

At the top of the Audacity main window, you will find the menubar as you know it from other programs. In the bar below, you have direct access to the software's central control buttons and the tools Audacity provides for editing sound. In the third bar, you can define which devices Audacity uses for input and output. Make sure you select the right microphone.

First Recordings

Click on the icon with the red dot to start a recording. Audacity will create a new audio track in the current project. When you speak into the microphone, a waveform will appear in the audio track of the Audacity project (Figure 1). At the same time, the microphone level in the middle of the toolbar indicates what level of volume is getting through to Audacity. To pause the recording, click on the button with the white square.

Figure 1: Audacity at work: In this example, the USB microphone connected to the computer provides a stereo track, so Audacity displays two waveforms.

The steps for recording the podcast depend on the quality requirements. In the simplest variant, just start a recording, talk into the microphone, export the resulting audio track to a common format, and publish the resulting file on the Internet.

However, if you use Audacity only as an audio recorder, you are neglecting many of its advanced features. For example, very few people are able to get through a long recording without glitches such as coughing, background noises, delay sounds (such as the classic "Uh?"), or slip-ups. Audacity offers various tools to eliminate these problems.

The most common task when editing with Audacity is to remove background noise and slip-ups. First find the position by clicking on the audio track at the approximate location and then clicking the green arrow in the upper left corner to start playback. The position of the cursor that was previously set with a click now starts moving through the audio track.

Once you have identified the location of the problem, click on the very beginning of the section you want to remove. Hold down the left mouse button and drag the mouse cursor to the right. This step creates a brightly highlighted area – you want it to extend the area to the end of the glitch. Press Delete to delete the selected item from the track.

Tip: If you notice during the recording that you have made a mistake, just pause the recording for a second. The pause button makes it much easier to identify glitches in the audio track when reworking the recording.