Last time we got into some of the basics of sound, discussing the two main attributes:
Frequency and Amplitude.
Today we're going to get a little deeper into this stuff so that we can understand how it relates to the music we make using tools like Reason.
OK. So, frequency is basically dealing with pitch, right? How high or low a sound is. Measured in Hertz (Hz). Let's listen to a few tones to recalibrate our ears:
So what we were listening to were pure tones. Here is a picture of what a pure 440 Hz tone (aka "Concert A") looks like:
What we have been looking at and listening to so far are what are called sine waves. Sine waves are basically pure tones - nice and smooth and even, no additives or preservatives. But, as with so many things in life, reality is almost never so smooth and even...
Here is what Concert A (aka 44oHz) looks like when played by a grand piano:
Whoa. Lots of stuff going on here. I should point out that this picture is zoomed way out, so we're not seeing the individual waves like we were in the picture of the sine wave. But my point is this: there is a LOT more than just a simple 440Hz sine wave playing when you hit the A key on a piano.
Major point #1: Almost no natural sound contains only one frequency.
You might be asking yourselves then, "What are the other frequencies?"
Short answer: harmonics.
OK, so I just lost about half the class with that last sentence. But it's really not that complicated. Check it out:
So, we're looking at the first 5 harmonics of a vibrating string. The first harmonic is what is called the fundamental frequency. The fundamental is like the "main note" being played. For example, in the picture of the piano note above, 440 Hz is the fundamental, but all that other stuff in the waveform is a bunch of harmonics:
1st harmonic (aka fundamental) = 440Hz
2nd harmonic = 880Hz (440 x 2)
3rd harmonic = 1320 Hz (440 x 3)
4th harmonic = 1760 Hz (440 x 4)
5th harmonic = 2200 Hz (440 x 5)
Every musical instrument has harmonics, but the amounts and combinations of these harmonics are unique to every instrument. This is why a guitar sounds like a guitar, a snare drum like a snare drum, Mariah Carey like Mariah Carey, etc.
Here is a comparison of a flute, a clarinet, an oboe, and a saxophone all playing Middle C (256 Hz):
As you can see, they are similar (they are all instruments from the woodwind family), but it is the unique harmonic content that gives each one a unique sound.
Major point #2: an octave is a doubling of frequency.
Remember our old friend the octave? A couple classes ago I described an octave as "a set of all the notes you can possibly play".
This is true. That is a musical way of understanding what an octave is.
But you can also look at it from a scientific perspective and see that everytime you go up an octave, you are doubling the fundamental frequency of the key that you started from.
Now that you know about octaves, see if you can answer this question:
Even-numbered harmonics are generally considered to be more musically pleasing than odd numbered ones. Why do you think this might be?
1st harmonic (aka fundamental) = 440Hz
2nd harmonic = 880Hz
3rd harmonic = 1320 Hz
4th harmonic = 1760 Hz
5th harmonic = 2200 Hz
Major point #3: Using electronic equipment (aka synthesizers), it is possible for humans to create all kinds of original sounds that don't exist in nature.
We will be getting deeper into this later when we discuss synthesizers, but for now let's just be aware that there are a handful of common types of sound waves that are used as building blocks in creating electronic sounds and instruments. They are:
1. Sine wave - Our old friend. The simplest of all sounds. A pure frequency.
2. Square wave - A tone with an infinite set of odd harmonics. Pretty harsh sounding, but it's a good material to start with when you're creating new sounds.
3. Triangle wave - A tone that also has an infinite set of odd harmonics, but they fall off in volume more quickly than the square wave.
4. Sawtooth wave - A tone that has all the related harmonics.
We'll stop here for the moment. In the next lesson we will learn about phase, filters and volume envelopes.
Oh yes.
OK. So, frequency is basically dealing with pitch, right? How high or low a sound is. Measured in Hertz (Hz). Let's listen to a few tones to recalibrate our ears:
So what we were listening to were pure tones. Here is a picture of what a pure 440 Hz tone (aka "Concert A") looks like:
What we have been looking at and listening to so far are what are called sine waves. Sine waves are basically pure tones - nice and smooth and even, no additives or preservatives. But, as with so many things in life, reality is almost never so smooth and even...Here is what Concert A (aka 44oHz) looks like when played by a grand piano:
Whoa. Lots of stuff going on here. I should point out that this picture is zoomed way out, so we're not seeing the individual waves like we were in the picture of the sine wave. But my point is this: there is a LOT more than just a simple 440Hz sine wave playing when you hit the A key on a piano.
Major point #1: Almost no natural sound contains only one frequency.
You might be asking yourselves then, "What are the other frequencies?"
Short answer: harmonics.
Harmonics are whole number multiples of a specific frequency.
OK, so I just lost about half the class with that last sentence. But it's really not that complicated. Check it out:
So, we're looking at the first 5 harmonics of a vibrating string. The first harmonic is what is called the fundamental frequency. The fundamental is like the "main note" being played. For example, in the picture of the piano note above, 440 Hz is the fundamental, but all that other stuff in the waveform is a bunch of harmonics:
1st harmonic (aka fundamental) = 440Hz
2nd harmonic = 880Hz (440 x 2)
3rd harmonic = 1320 Hz (440 x 3)
4th harmonic = 1760 Hz (440 x 4)
5th harmonic = 2200 Hz (440 x 5)
Every musical instrument has harmonics, but the amounts and combinations of these harmonics are unique to every instrument. This is why a guitar sounds like a guitar, a snare drum like a snare drum, Mariah Carey like Mariah Carey, etc.
Here is a comparison of a flute, a clarinet, an oboe, and a saxophone all playing Middle C (256 Hz):
As you can see, they are similar (they are all instruments from the woodwind family), but it is the unique harmonic content that gives each one a unique sound.Major point #2: an octave is a doubling of frequency.
Remember our old friend the octave? A couple classes ago I described an octave as "a set of all the notes you can possibly play".
This is true. That is a musical way of understanding what an octave is.
But you can also look at it from a scientific perspective and see that everytime you go up an octave, you are doubling the fundamental frequency of the key that you started from.
Now that you know about octaves, see if you can answer this question:Even-numbered harmonics are generally considered to be more musically pleasing than odd numbered ones. Why do you think this might be?
1st harmonic (aka fundamental) = 440Hz
2nd harmonic = 880Hz
3rd harmonic = 1320 Hz
4th harmonic = 1760 Hz
5th harmonic = 2200 Hz
Major point #3: Using electronic equipment (aka synthesizers), it is possible for humans to create all kinds of original sounds that don't exist in nature.
We will be getting deeper into this later when we discuss synthesizers, but for now let's just be aware that there are a handful of common types of sound waves that are used as building blocks in creating electronic sounds and instruments. They are:
1. Sine wave - Our old friend. The simplest of all sounds. A pure frequency.
2. Square wave - A tone with an infinite set of odd harmonics. Pretty harsh sounding, but it's a good material to start with when you're creating new sounds.
3. Triangle wave - A tone that also has an infinite set of odd harmonics, but they fall off in volume more quickly than the square wave.
4. Sawtooth wave - A tone that has all the related harmonics.
We'll stop here for the moment. In the next lesson we will learn about phase, filters and volume envelopes.
Oh yes.
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