Podcasting

Podcasts are the newest way of broadcasting content to the masses. By creating a podcast, content can be delivered to students automatically, where it can be listened to on their computer or downloaded to their portable MP3 player. While the mainstream media is rushing into this field, the educational field is just starting to explore this technology. This site will explain how to create a podcast and discuss how this technology can be used in teaching.

Recipe for Podcasts

There are a number of parts to a podcast. There is the actual audio file that is recorded using a computer and microphone, or using a digital recording deck. This audio file is placed on a web server. This file can be delivered to students in two ways:

1. RSS feed -- an .xml file used by certain browsers and media players to subscribe a user to a podcast. When new podcasts are recorded, they are automatically delivered to the student via applications like Apple iTunes and iPodder.
2. HTML -- a traditional web web page with a link to download the podcast. This method requires the student to actively retrieve the content.

Recording a Podcast

As with any audio and/or video recording, it is important to do it right. Good sound quality is only achieved when the proper tools are used in the proper setting. The Audio & Video Series has a session called Creating High Quality Content that provides helpful information on techniques and suggestions.

The basic properties of a good recording depend on what kind of recording is being performed. For the most part, a recording with a fair dynamic range- low background noise and clear, audible audio of the subject is desired - be it a speaker or frog calls. The basics to remember are: selecting a good location, using the appropriate equipment and microphone, and getting good levels.

Selecting a Good Location

As they say in business: location, location, and . . . location. If it is possible to control where recordings are made, try to find a location that has low noise levels and has a lockable door so people can't walk in. Computers and air conditioning with the low level hum of electricity and fans are enemies when trying to get a good recording. Access to a sound recording studio is, of course, the best case scenario! However, many of us don't have access to high end recording studios and can't completely control the location. To some extent, this can be alleviated by using an appropriate microphone or in post when editing.

Using the Appropriate Microphone

When buying a stereo, they say the most important component is the speakers because it's the speakers that are actually physically reproducing the sound. For recording audio, the most important component is the microphone because it determines what the audio sounds like when it is recorded.

Shotgun

It is possible to exaggerate the directionality of cardioid type microphones. The shotgun is extremely sensitive along the main axis, but possesses pronounced extra lobes which vary drastically with frequency. In fact, the frequency response of this microphone is so bad it is usually electronically restricted to the voice range, where it is used to record dialogue for film and video.

Lavaliere

The lavaliere (or lav) microphone is commonly used with wireless systems so a speaker can move around freely without being tied to a microphone stand or podium. The pickup range is small and the mic is usually clipped to a shirt or lapel.

Choosing a Recording Device

To save time, recording should be done in a digital mode, if at all possible. This would include recording directly to a PC using audio recording software, or to a digital recorder that save the recording to an mp3 format. Traditional tape recorders can be used but digital recording is preferable.

Podcast Creation Software

To record, edit and clean up audio files, audio editing software is required. Some programs, like Audacity, only allow for audio editing. Other applications, like ePodcast Creator and Propaganda, also create the necessary .html and .rss feeds. This section will review these titles and provide some recommendations.

Audacity

Audacity is a free application for audio recording and editing. It is available for Mac, Windows and Linux platforms. It supports multiple tracks, and comes with a variety of tools necessary to clean up audio files. Files can be exported to MP3 format with the installation of a LAME MP3 plugin, which is also free. The tool is pretty easy to use, and is recommended highly. Users will have to supplement this tool with an application like Podcaster RSS Buddy or FeedForAll to create the necessary RSS feed, and manually publish it to a server.

ePodcast Creator

ePodcast Creator was created mainly for recording radio shows with audio commentary at the beginning and in between songs. However, it can be use for recording and editing of an audio track. The interface is a little difficult to understand, and the connection between the editing and recording features is not obvious. When editing a file, it is unclear what needs to be done to return to the main interface. It also has the capability to create .html and rss feed files and will publish those files to a web server. It is important to note that it only supports FTP transfer of files. Since servers like Learn@UW and MyWebSpace use secure WebDAV file transfer protocol, this application could not be used to upload files to these servers. The application costs $90 and is only available on the PC.

Propaganda

Propaganda is similar to ePodcast Creator in that its primary purpose is to create radio shows with audio commentary. The interface is much clearer than ePodcast Creator, but much of this is due to the lack of audio editing. Audio editing is supported however. There is a very nice timeline that allows for multiple tracks to be arranged and cross-faded. Again, this is intended to be an radio broadcast tool, these features are not all that important in an educational market. Like ePodcast Creator, this application is only available on the PC and costs $50.

FeedForAll

FeedForAll is a tool used to create an RSS feed for a podcast. The interface is difficult to understand and requires a good deal of knowledge regarding the structuring of RSS feeds. Additionally, while the application has the ability to publish the rss file to the server, it assumes the audio files either already reside on the site or will be moved to the correct location manually. Again, it is worth noting that the publishing feature for the application only supports FTP connections, not WebDAV. While the application is available on the PC and Mac, the Mac version is in beta and currently not worth using. The cost is $40.

Podcaster RSS Buddy

Podcaster RSS Buddy is another tool used to create an RSS feed for a podcast. Like FeedForAll, this application requires that one understand the basic elements of an RSS feed. Additionally, while the application has the ability to publish the rss file to the server, it assumes the audio files either already reside on the site or will be moved to the correct location manually. Again, it is worth noting that the publishing feature for the application only supports FTP connections, not WebDAV. While the application is available on the PC and Mac, the Mac version is in beta and currently not worth using. The cost is $40

Podcast Receiving Software

Apple iTunes

Apple iTunes, available for both Mac and Windows, allows users to subscribe to RSS feeds and have those broadcasts downloaded to an iPod, or played on the computer.

iPodder

iPodder, available for both Mac and Windows, also allows users to subscribe to RSS feeds and listen to the broadcasts on the computer via the appropriate media player.

Campus locations for broadcasting Podcasts

To host a podcast, files need to be hosted on a web server. Campus has several options available for web hosting.

MyWebSpace

All faculty, staff and students have access to web server space on the MyWebSpace server. Disk space is limited to 100 MB and accounts are restricted to a 200.00 MB per hour bandwidth limitation. This means, for example, that a 5MB mp3 file could only be downloaded 40 times in any given hour.

If copyrighted materials are being distributed for instructional purposes, these files need to restricted to registered students of a course. Currently, MyWebSpace does not load course rosters into MyWebSpace, and therefore, instructors would need to manually add all students into a group within MyWebSpace and restrict those materials to members of that group.

Learn@UW

Learn@UW is a natural place to host course-related files, however, podcasted files cannot be hosted within Learn@UW course files folder due to authentication problems with the RSS feeds. Files can be located in the MyHomepage portion of Learn@UW, however. It is important to note, however, that this portion of Learn@UW is not password protected, so there are some issues with regard to hosting copyrighted materials in a non-password protected environment.