Recording and Editing Audio with Audacity

Transcription

1 1 Recording and Editing Audio with Audacity Audacity is free, open source software for recording and editing sounds. It is available for Mac OS X, Microsoft Windows, Linux, and other operating systems. Why should I try Audacity? It is a free and easy way to create an audio clip for your Canvas course site with just an inexpensive microphone, a sound card (pretty standard on all computers) and speakers. What can I do with Audacity? You can use Audacity to: Record live audio. Convert analog audio from tapes into digital recordings or CDs. Edit Ogg Vorbis, MP3, and WAV sound files. Cut, copy, splice, and mix sounds together. Change the speed or pitch of a recording. And more! Recording Audacity can record live audio through a microphone or mixer, or digitize recordings from various analog sources, like cassette tapes. With some sound cards, it can also capture streaming audio. Record from microphone, line input, or other sources. Dub over existing tracks to create multi-track recordings. Record up to 16 channels at once (requires multi-channel hardware). Level meters can monitor volume levels before, during, and after recording. Import and Export Import sound files, edit them, and combine them with other files or new recordings. Export your recordings in several common file formats. Import and export WAV, MPEG audio (including MP2 and MP3 files). Export MP3s with the optional LAME encoder library. Create WAV or AIFF files suitable for burning to CD. Editing Easy editing with Cut, Copy, Paste, and Delete. Use unlimited Undo (and Redo) to go back any number of steps. Very fast editing of large files. Edit and mix an unlimited number of tracks. Fade the volume up or down smoothly with the Envelope tool.

2 2 What will I be learning in this introductory workshop of Audacity? In this workshop, you will be introduced to the very basic features of Audacity like how to use the sound recording and editing features of Audacity. You will also do a simple edit of recorded audio and have the option of creating an mp3 file of the finished product. [For this tutorial, we will be using only the basic features of Audacity.] After you have downloaded your free Audacity ( and the LAME MP3 encoder, which allows you to export your Audacity files as MP3 file ( ); you will be ready to use Audacity. Setting up an External Microphone For recording, it is usually recommended that you use an external microphone for best results. It is important that you set up the microphone for the computer before launching Audacity. First connect the external microphone to your Mac or PC. On a Windows PC: 1. Click on the Windows button and select Control Panel from the menu. 2. Next open the Sound control panel. 3. Click on the Recording tab and select the external microphone you have connected and click OK.

3 3 On a Mac: 1. Click on the Apple menu apple and select System Preferences. 2. Next, click and open Sound. 3. Click on the Input tab and select the external microphone you have connected to your Mac. Close the System Preferences window to finish.

4 4 Creating an Audacity Audio Project Below is what the Audacity interface looks like. When you launch Audacity, or select New from the File menu, the workspace interface is created as an Audacity project. Before beginning work in a project, make sure that the microphone you connected is selected in the microphone menu. For our workshop we will be focusing, mostly on the toolbar area: Let s begin by clicking the Record button. (Be sure that your microphone and speakers are in the ON position.) Notice the audio line as you begin to speak. If you need to stop recording for a moment, press Pause. Press Pause again to continue recording.

5 5 When you have finished recording, click the square Stop button. Click the Return to Start button (this will re-wind your recording) and then the Play button to listen to your recording. To save the project, select Save Project from the File menu. It is recommended that you save as a project before doing any editing to ensure that the recording is saved. To export the project to a particular sound format, go to the File menu and select Export. (MP3 files seem to work best for students, if you are posting your audio file in Blackboard.) The Export window will appear and you can select the format for the finished exported file. Exporting Project-PC Exporting Project-Mac The Options button in the Export window allows you to select the quality level of the mp3 export. Save Options-PC Save Options-Mac

6 6 In the menu to select Quality, selecting a higher bitrate increases the quality but increases the file size too. If the recording is voice only, you can select 64 or 96 kbps. If the recording needs better quality, due to the addition of music as an example, you can start with 128 kbps as a minimum. Click OK to finish the selection. Click Save to continue with the export. You will probably see another window appear to enter metadata for the export, but can just click OK to continue. Your file is now saved and ready to be shared.

7 7 Editing an Audacity Project Modifying an audio file Open Audacity and import the audio file that that you wish to edit. To import, click on the File menu and select Audio from the Import submenu. Make sure your computer sound is on, and adjust your speaker or headphone volume. Trimming Recordings To trim a portion of the audio file, play the sound file a few times to see where the portion you would like to remove resides visually in the wave pattern. Then, using your mouse, click and drag to carefully select that section of the audio. Then press the Delete (Mac) or Backspace (PC) key to remove the selected part of the sound file. New Project From Selections You can also use a selected area to copy and paste sections of a recording into a new project. After selecting a portion of a recording, select Copy from the Edit menu. Then open a new project, and paste the selection. Now you can work on the clipped portion separately.

8 8 Amplifying Audio If an area of the audio file is being heard a low level, you can raise the level using the Amplify effect. To amplify, we first find and select the section, then select Amplify from the Effect menu. Begin with the default amplify settings to see how much more the volume level is raised. You can always undo (control-z on the PC, command-z on the Mac) and start over to adjust the amplification levels to suit your needs. Creating Fades You can also have the audio file fade in or out at any point in the file. This is useful at the beginning or end of an audio file, especially a live recording, to create a smooth entry and exit to the recording. First select the portion you would like to fade. Next, select Fade In from the Effect menu.

9 9 Once completed, this should make this section of the wave pattern look bullet like, with the audio increasing from zero volume. Listening to Selected Audio If you are doing transcriptions of recordings, it is often easier to listen to sections of the recording at a time. To do this, select a portion and click on the Play button to play the selected section. What is useful about this feature is that Audacity will only play through the selection and each time you click Play, it will again play from the beginning of the selection, not the recording. Adjusting Recording Speeds Also useful in transcription is the ability to adjust the speed of the recording or selections of the recording to help the listener accurately transcribe. Either select all or some of the recording and select Change Speed from the Effects menu. Decrease the speed by pushing the slider to the left into the negative values. You may need to try different values to see which speed will provide the best clarity in listening for transcription.

10 10 The last thing left to do is play the entire file again to make sure all of our edits sound correct. Use the Skip to Start Button (just left of the PLAY button) to "rewind" the sound file. Play the file a few times to make sure it sounds as expected. None of the edits has yet been saved. Before moving on click on the File menu and select Save to be sure your edits to the project are preserved. To create an MP3 from the edited project, select Export from the File menu and export the final product. Learn how to create a file with multiple tracks. Be sure that you have both files available on your desktop. Open Audacity and create a new project by selecting New from the File menu. To import the tracks, which can include voice as well as music, click on the File menu and select Audio from the Import submenu. You will then see the two tracks in the project, in this case the first track is mono and the second stereo. Note the and + signs to the left of the files. Move the arrow to either the plus or minus depending on how loud you want each file to sound. By adjusting the volume of each track you an balance the tracks, in this case a vocal and music track, so that the music track can be set to be heard in the background.

11 11 Using the tools we have already demonstrated, trim and adjust the project to fit your needs. In this example, we have trimmed a portion from the beginning of the second track and created a fade in. One other tool may be useful in your work with multiple tracks is the Time Shifter. Usually Audacity defaults to the selection tool to select portions of audio but with multiple tracks you can select Time Shifter. This will allow you to click and drag a clip to re-align it in relation to the others in the project.

12 12 Click the Play icon to listen to your combined file. When the two files are blended with the balance you are looking for, use the File menu and select Export to create the mp3 file. After clicking Save in the export dialog box a window to enter metadata for the file will popup. For most purposes, you can simply click OK to continue. A final message will pop-up indicating that the export will mix down the multiple tracks. Click the OK button to finish saving the file.