EDITING AUDIO ON A COMPUTER

Looking at the previous pages you would be correct to conclude that editing audio on a minisdisc recorder is a fussy, complicated business involving a lot of button presses & procedures. The processes can hardly be described as intuitive. Added to this, different manufacturers use different terminolgies & often the procedures will vary from machine to machine. This is where computers come to the rescue.

Computers & digital recording have revolutionised audio editing in much the same way that digital video has revolutionised film editing. The most important element of this is the graphical user interface (abbreviated to GUI.)

On a computer you can see (& hear with speakers attached) the waveform you are editing. On a minidisc recorder you are editing based on what you can hear alone. The computer allows you to zoom in & out so that you can see what you are editing in greater or lesser resolution & this makes the process much easier. Of course computer software has to be mastered & you will have to learn to "read" a wavefrom, but as we shall see, that is not too difficult.

Let's look at the piece of audio we were editing earlier.

Track1withexplanation

Now you can see what is being said, it is far easier to understand what is going on. Time is travelling from left to right. Where there is a very thin black line there is silence. "Blobs" of black are the words & the distance above & below the centreline indicates the volume of the words.

So you can see that the "f" of "five" is probably the loudest sound we have in this recording. You can also see that the noise before the cough at the start is comparatively quiet.

Lets have a look at carrying out the same editing tasks as we did on the minidisc earlier only this time using a computer. The software is Digidesign's Pro Tools 8 although the same results can be achieved using virtually any audio editing software. (Very often this type of software is called a DAW which stands for digital audio workstation.)

Pro Tools has a number of different tools for editing audio. At the moment we just need to know about three of these. The grabber, the selector & the trimmer.

PTtoolsbar

The Grabber - is used to select an entire region with a single mouse click. If you click & drag, regions can be moved along the timeline horizontally or moved to different tracks if dragged vertically.

The Selector - is used to position the playback cursor or to select an area in a track - if you click & drag - to edit or playback.

The Trimmer - is used for trimming excess audio from the beginning or the end of a region. This allows you easily shorten or expand an audio region.

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