Audio Editing: Digitizing Audio from Different Sources: Instructional Systems Technology<br> Lab Reference, School of Education, Indiana University at Bloomington

Instructional Systems Technology
Lab Reference

1. Follow prerequisite job aid

2. Launch Sound Forge and select source

In the "Playback" pulldown window, select your playback device router numbers (for instance, the minidisc router numbers are 5 and 6)
Click on "Ok"

3. Set up audio levels

Conform that it saves 44, 100Hz, 16 bit, Stereo at the top. (If it does not, click on the "New" button, adjust to these settings)
Click on the "Monitor" window so that a check mark appears there
Play the source audio and adjust the volume so that the loudest audio does not go into the red
Cue the audio source back to the beginning

4. Digitizing the audio selection

Click on the red "Record" button (next to the "Prepare" button
When the selection is finished, click on the black "Square" to stop recording.
Click on the "Close" button in the upper right corner (you should now see the wave from that you just recorded)

5. Adjusting wave form

6. Changing from stereo to mono

Under the "Process" menu item, select "Channel Converter" (After Sound Forge does its processing you will see one wave form instead of two)

7. Delete unwanted selections

Play audio clip by clicking on the triangle pointing to the right
Identify the unwanted portions of the wave form
Drag the cursor over that selection
When the appropriate section is highlighted, press the Delete key
Play the revised wave form and if it is not correct, select "Undo" from the Edit menu and do again.

8. Reducing sampling rate

Under the "Process" menu item, select "Resample"
In the Resample window, expand the "Name" window by clicking on the arrow.
Select the desired sample rate and then click "Ok"
Sound Forge will work on the file previously sampled at 44 and reduce it to a file of the new sampling rate (you may see little change in the wave form)
Play back the file, listening carefully for losses in articulation or some increases in noise.
If you perceive undesirable changes, select "Undo" from the Edit menu and resample again at a higher rate.

9. Save your file

Once you have an acceptable audio clip, select "Save As" from the "File" menu item
If you are working on a Windows-based project, save the file as a Wave file
If you are working on a Mac-based project, save the file as a Macintosh AIFF (*.AIF, *.SND) file