Play the class the same ten seconds of video three times: silent, then with music, then with music and a voice over the top. Ask what changed.
Nothing on screen moved. The picture was identical every time. What changed was the sound, and with it the whole meaning.
Today you cut and shape a clip. Next lesson you add your own voice to it.
Download the practice audio file (MP3). It opens with a creaking door for roughly ten seconds, then music. That creak is what you cut first.
Almost every piece of digital media uses three kinds of sound, often at the same time.
| Kind | What it does | Example |
|---|---|---|
| Voiceover | Carries the information. | Someone explaining what you are looking at. |
| Sound effects | Make actions feel real. | A door creak, a notification ping, footsteps. |
| Music | Sets the mood before anyone has said a word. | Slow strings under bad news; a bright loop under a promo. |
The green shape you are about to work on is a waveform — a picture of the sound. Tall parts are loud, flat parts are quiet. You edit by selecting part of that picture.
AudioMass runs in the browser. Nothing to install, no account to make.
Two cuts: take the creak off the front, then bring the end in so the whole clip runs exactly thirty seconds.
| Cut | Target |
|---|---|
| From the start | Remove the first 10 seconds, the creaking door |
| Final length | Exactly 30 seconds |
A clip that starts at full volume sounds like an accident. A fade tells the listener the sound was meant to begin.
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