In the first half of this article I covered how to invite a guest for an interview, prepare and record the interview, and manage the interview to keep it on track and interesting. In this part I'll show you how to edit the interview audio on your computer, and share some tips from the pros that you can use in your own interviewing.
There's only so much you can do in the editing room with bad signal. The best way to get high-quality audio is to record it correctly in the beginning. That means preparing the space, yourself, your guest, and the equipment.
First, check out the room. Can you turn off the air conditioning or furnace blower? If so, you should. Are there periodic noises, like computer fans or buzzing fluorescent lights? How about intermittent noise, like telephones or door slams? Try to reduce that as much as you can. Turn on your recorder and monitor the room. You may be surprised at what it picks up.
After removing environmental noise, take a look at yourself and the interviewees. Do they have noisy clothes, like jackets, that can be removed? How about jewelry, which has the bad habit of clinking?
Next, check your microphone setup. If possible it should be on a stand to reduce handling noise. And it should have a pop screen to stop the popping that comes from the rushing air of hard consonants like P and B (see Figures 1 and 2). Commercial pop screens are easy to set up, but you can also make your own.
Figure 1: The MXL V63MBP mic, part of the company's Computer Desktop Recording Kit, comes with a convenient desktop stand.
Figure 2: A pop screen, like this one from Popless, helps prevent explosive P and B sounds from ruining your recordings. Note the elastic shock mount on the mic as well. It minimizes vibration pick-up.
Next, check your levels to make sure you're getting the most volume you can without clipping. And let your interviewees know that they should stay in the same relative position to the microphone, unless you're using a handheld mic and controlling the position yourself.
Last, be sure to get a sample of the ambient noise in the room for use in editing later. Five to ten seconds should suffice.
Once you have the audio recorded, you will need to edit it into a produced form for your podcast. The extent of the editing is up to you, but you need to make sure that your guest knows beforehand what type of editing will be done. In the examples below, I'll use Audacity, the free audio editor for Windows, Mac OS, and Linux.
When you've got your guests thinking, they will often pause and say "um" or "hmm." Everyone does it, some much more than others, and it's annoying to listen to. It's ethical to speed up the interview by removing the ums. Figure 3 shows the audio waveform in Audacity with the um selected. Figure 4 shows the waveform with the um removed.
Figure 3. The um is selected.
Figure 4. The um is deleted.
Until you get the hang of removing sounds cleanly you should try removing more or less audio around a single um to see what sounds the most natural. Often people will trail an um into the beginning of their first word. Finding where to cut the um in that case can take some experimentation. It helps to zoom way in on the waveform and cut on zero-crossings, the points where the waveform crosses the center line in the diagram, meaning that the level is zero. Many audio editing programs can snap the cursor to zero-crossings automatically, and some will automatically smooth the audio surrounding the edit point with a brief crossfade.
Matching the wave shape on either side of the cut can help smooth the transition as well. For example, suppose the waveform is falling toward the zero-crossing at a 60-degree angle just before the beginning of your cut. Try to put the end of the cut at a point where the waveform falls below the zero-crossing at 60 degrees. That will produce a linear transition from high to low. (For more waveform-matching tips, see the sidebar "Extreme Audio Editing.")
Isolated ums are fairly easy to remove, but sounds that overlap the speech, like microphone noise, pops, or tongue clacks from dry mouth, aren't as easy to fix. While you're recording the interview keep in mind how you'll edit it later. And if those problems occur, let your interviewees know, and give them an opportunity to stop, fix the problem, get a glass of water, and start again on the same question so that it's easier to edit later.