In this lesson we teach you some basic audio terms that will help you throughout this tutorial. We'll also inspect the various
aspects of the sound wave so you may indentify the different parts the will play in the over-all scheme of things.
Grab video code:
Let us go ahead and open a couple of files that I will use to illustrate some of the concepts in this lesson. Navigate again to your desktop, your project files, and the media resources folder. I am going to load whistle and Zoom basol intro. Let us view whistle first.
Let us define some basic audio terms which will be useful to us as the series moves forward. First of all, amplitude. Most simply put amplitude is the loudness or the volume of a sound. More specifically, it is the distance between the crest or the top, and the through or the bottom of a waveform at any given point in time.
Frequency is most simply the pitch of the sound. It is the note that you hear. More specifically, it is the quickness with which a wave travels from a crest through a through and back to a crest again. Frequency is measured in hertz or the number of times to complete cycle takes place in a single second.
Phase is measured in degrees. It is the current position along one vibration cycle. It is also commonly used to compare two wave forms against one another. As in noting that one wave is any number of degrees out of phase with another. Being in phase refers to a state in which the crest and throughs are aligned in time.
Tambour is the sonic character of a sound regardless of its current pitch. It refers to the difference between instruments. For example a violin and a piano, which obviously sound different despite the fact that they might be playing the same note. Over tones are the simple frequencies that actually make up the sound that you hear. Typically if you view a sound in a spectral analyzer like we have down right here in Soundbooth, you will see a series of horizontal lines at any given signal. Often these lines will be cascaded above one another. Each one of those lines is known as an overtone. If you selectively playback the individual overtone in a sound, that leads sound pretty much just like a simple sign wave. But when each of those overtones are combined, they create a unique totality of the sound that we hear.
Take a look at this example that we have got here. This is a recording of someone whistling. Let us take a listen.
You can see that there is one primary overtone right here. This is what we could call the fundamental. This is the majority of the sound that we hear when play it back. But you can also see the secondary little ghostly overtone up here. This is one of the harmonics of the sound. If I move over here to my Tasks Panel, close the clean up audio menu and open remove a sound.
I will make sure that Play selected frequencies only is selected. With this options selected, I will move up to my frequency selection tool which is up here in Soundbooth’s toolbar.
And I will just select this one fundamental here and we will play back again.
You can hear that it sounds very, very similar because in this case, this one overtone is the majority of the sound. But if we select this secondary one up here, we will hear specifically what it adds to the overall tone.
It is quite faint but you can hear that the really high pitch ringiness of the whistle is provided not by this main fundamental, but by this secondary harmonic up here. Let us take a look at a slightly more complicated example.
Let us listen to this clip.
If we select just one of these overtones here at the bottom, and play it back.
You can hear how it is only a very small portion of the overall signal. Let us pick something a little higher that still has a fairly narrow band width.
You can see how the sound is pretty much indistinguishable when you have such a narrow band selected. But when I start to combine large amounts of frequencies together—
You can hear that the tambour of the voice begins to come back.
[Demo] Again the entirety of the signal sounds perfectly normal.
As we select frequencies, we are choosing a band which extends across the clip. As we shrink and expand the size of the band we are playing with, you could say