Creating Podcast Narration Tracks
One of the challenges in creating your own podcasts is recording the narration track. Speaking clearly and accurately is difficult for many people to get right without many attempts and false starts.
An easier approach is to use the built-in text-to-speech abilities of Mac OS X and Automator to convert written phrases to audio files you can drag directly into your GarageBand podcast project.
Listen to this example podcast using rendered clips of two voices from the Cepstral collection:
Testing the Text
The first step is to refine and test the text to use for the narration clip. If you haven't done so, download and run the installer containing the workflows used to generate the audio clips.
While holding down the Option key, select the Test workflow from the Voice to Audio sub-menu in the system Script Menu located at the right of the menu bar. The following workflow will open in Automator:
Enter the text you want to render to an audio clip in the first action in the workflow, and then select a voice from the popup menu in the second action. Run the workflow in Automator. Refine the text until the phrases sound well paced and correct. Adding punctuation, such as a commas or semi-colons, can give the phrases better timing.
NOTE: The example podcast on this page uses voices from the Cepstral collection. Another great set of voices is available from Acapela. All of these third-party voices are very high quality and work well as narration tracks.
Rendering the Text
After you've refined the text, open the Generate workflow from the Voice to Audio sub-menu in the system Script Menu, by holding down the Option key while selecting the menu item.
Copy the narration text from the previous workflow into the first action in the Generate workflow. Choose the voice to use in the second action, as well as enter a name and location for the audio file to be created.
By default, the Text to Audio File action uses the built-in text-to-speech abilities of Mac OS X to render the text as an audio file in AIFF format. Since GarageBand cannot accept a voice track in this format, we'll have to convert the AIFF file to the MPEG format which is used by GarageBand. Set the parameters for the Export to MPEG Audio action to those show in the illustration above. (This action requires QuickTime Pro be activated on your computer.)
Run the workflow, and the rendered text will be exported and reopened in the QuickTime Player.
Placing the Audio Clip
The last step is to add the clip to a corresponding track in an open GarageBand podcast project. With the GarageBand project open behind the QuickTime Player, drag the file proxy from the title bar of the QuickTime movie to location on the voice track timeline, and drop the proxy icon. The contents of the audio clip will be imported and displayed at the chosen location.
NOTE: be sure to place the voice clip on the appropriate track: a male voice clip on the Male Voice track, or a female voice clip on the Female Voice track.
Follow the previous steps with each narration to be added to the podcast.