Audio narration (voice-over) for a video


Easy version

The best way to record your voiceover is to plug a mike into a computer and record into an audio file on the filesystem. Then you can transfer that audio onto a videotape using manual insert editing or through a nonlinear editor.

First, I highly recommend that you write out your voiceover *before* ever recording any video. Write down what you want to say, then figure out exactly what you want to show during each section. Time out how long each section takes to say, speaking slightly slower than normal conversational speed. This can be an iterative cycle, until your video and audio ideas match up.

I realize this sounds like a lot of work, but it will make your life and video *much* better if you know how long each video segment should be and make an effort to create them with the correct timing. It's particularly an issue when you're recording interactive sessions off the screen, where if you don't make a real effort to do things according to schedule you'll have boring video that lasts way too long.

If you record your soundtrack before creating your video, then you can play that back to yourself as a timing aid when you're recording the video segments.


More detail

Voiceovers should be recorded in a quiet room, since excessive background noise will get picked up by the microphone. The video lab is a very noisy room, since there's a lot of equipment with fans and the ventilation system needs to be on high all the time to avoid equipment damage. Do not record your voiceover there.

Finding the right mike to plug into a computer

To record your voice to a computer, you can either use the black LabTek microphone, or use the combination of the studio-looking silver mike and the Symetrix preamp box. The black mike outputs a "line-level" signal which can be plugged directly into a computer; but the silver mike outputs a "mike-level" signal which has to be to be amplified to line-level be the preamp before it can be fed into a computer. Though it is a more complicated setup, we recommend the silver mike because it has better sound quality.

The default "home" for the silver mike-preamp combination is the conference room. The silver mike can usually be found on top of the cabinet, and the box directly connected to the mike is the preamp. The box after the preamp is called a "matchbox" which provides even more amplification when you want to record voice in the conference room onto moviola. But if you just want to record your voice onto any other Indy elsewhere, you don't need the matchbox. So you should find the plug on the matchbox that says "IHF Input" and disconnect the wire from there. This is the output of the preamp that can almost be plugged into the mike input of an Indy. We say "almost" here because the connector at the end of the wire doesn't quite fit the mike input of the Indy. You need to add a converter to it. And for your convinience, we've taped an appropriate converter on the top the preamp box. Just make sure when you're done, tape the converter back to the preamp box. There are a couple of buttons on the preamp and they should all be at the "up" position (rather than "down"). The "gain" knob for "microphone 1" is the only knob you might want to turn in the recording session to give you the disired signel level. According to the tests we did a reasonable start position for the knob is between 40~50dB, if the Indy's audio mike input level slider is left in its default middle position.

Recording your voice

In this section, we when say "microphone" or "mike", it applies to either the black LabTec microphone, or the simlver mike-preamp combination. Plug the microphone into the mike input of the computer of your choice (like your office machine). Plug a pair of headphone into the phones jack (to avoid feedback). If it's a PC, try using the CoolEdit software downloadable from http://www.syntrillium.com/cooledit. You'll probably want to run the noise cancellation option, I've had good results with that. The nice thing about the PC approach is you can bring your laptop into a very quiet room, like the conference room (no fan noise). If it's an SGI:

Additional notes

If you're doing audio last instead of first and the timing is delicate, you'll need to see the video while you're speaking. If you're using a nonlinear editor, just make a movie file of the video and play that back using movieplayer on the SGI or its analog on a PC. If you're putting it directly on videotape, you could roll the big video cart from 392 into your office and play the tape on that. If you're mastering on Digibeta, you'll need to dub yourself a VHS copy since the only digibeta deck is in the video lab.

Old-style recording directly to tape

The old way of making voiceovers was to record directly into the audio channel of the 3/4" UMatic Play deck. (*Not* the record deck.) I highly recommend going the nonlinear route instead. But, for the masochistic, here's the relevant information:


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Last modified: Sun Jan 30 18:16:05 PST 2000