MUSIC THEORY - Lesson 2 - Sound pitch

Andrei Moraru

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There's a pitch perfect joke in this one, isn't there?

  1. Topics of discussion
  2. Sound pitch explained

1. Topics of discussion

In this thread, we're going to talk a bit about how we are able to distinguish notes from one another, even though they have the same name. So, let's have some fun.

2. Sound pitch explained

When it comes down to sounds and notes, each and every note can be represented as a sine wave. And since the A note is the one that kicks of the musical alphabet, let's take a look at an A4 note, but as a sine wave:

sine.png

Beautiful, ain't it? As you can see, the visual representation is a sine wave which has various places where it either hits a maximum value, 0, or a minimum value. And as you can see, I've labeled an area as a wave cycle. Basically, a wave cycle begins at the place where a sine wave hits 0 and then continues its ascending towards the maximum value and ends in the place where the wave once again hits 0 after rising from the minimum value.

Why are wave cycles important you ask? Well, the number of complete wave cycles a sine wave makes in a second gives us the frequency of that wave. And frequency is the measuring unit which helps us quantify a sound pitch. Frequencies are measured in Hertz (Hz).

So what is this pitch we speak of? Well, a complex definition would be something along the lines of "it is a subjective attribute of a sound, which allows us to differentiate between different sounds". The simpler definition refers to how high we perceive the sound. The higher we perceive the sound, the higher the pitch associated to the sound is and consequently the higher the frequency.
The concept of frequency is also important because of a certain term called octave. Last time I told you that when learning a scale, we usually start with a note and end with the same note but an octave higher.
Basically, an octave refers to the musical interval between a certain note and another one which has a frequency either halved or doubled. This is why the perceived sound is the same, only lower or higher. Last time I also told you that you may encounter notes labeled something like C4, with 4 being the octave in which that C note is located. This particular C note is also knows as middle C, because on a piano it's the note located at the exact center of the piano keyboard.

So how many octaves are there you ask? And how does sound perception relate to frequency? Well, the human ear is usually capable of perceiving sounds with frequencies between 20 Hz and 20 kHz (some can even hear sounds with frequencies lower than 20 Hz) and in this frequency interval we have a total of 10 musical octaves. You can take a look at this table if you want to see the frequencies for octaves 0 to 8. Yeah, there's an octave 0. I always assumed it's because C0 has a frequency lower than 20 Hz. You probably won't need to worry about that octave though, despite the tendency of some metal musicians to lower their guitar tuning to the point of needing 5 bass guitars to play their songs.

Some of you may be wondering why this is important. And the answer can be boiled down to harmony. These notes have the frequencies and pitches that they have because they are the values researchers have come to realize are the ones that provide the best experience to the human ear. And no, you don't have to memorize these values, nor use them when tuning your instrument. There are professional tools and people for such a matter should you not know what you are doing.

That about wraps it up for this tutorial. Next up, we're gonna take a look at musical sheets and start reading some music. See you then.
 

Lindsey

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"Despite the tendency of some metal musicians to lower their guitar tuning to the point of needing 5 bass guitars to play their songs."
😂😂😂
 

Jak Angelescu

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@Andrei Moraru I see you have 4 lessons so far, is that right? Can you please PM me the lessons you have posted and categorize them as beginner, intermediate or advanced lessons so I can now move them to the appropriate spot? Thanks!
 

Jak Angelescu

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I like these. Gonna read them more often. This one has neat info that I didnt know. Like the 10 octave thing. That's a TON of notes. And the middle c .. one question. Which one is that in the guitar? Closer to the bottom string I'm thinking.
Middle C on a guitar depends on what position you're in. In first position it's on the second fret, B string
 

Andrei Moraru

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Yeah that's the one I thought it would be. That's good to know when j eventually get a piano lol
Pitch wise yeah, that is the note, as Jak said.

However, when it comes to guitar music sheets, the A string 3rd fret C is considered the middle C note.

This has to do with the fact that guitar sheets only really use the G clef on their staffs. And in in order to still be able to read them sheets without drowning in leger lines, this convention was put in place.

You can take a look at lessons 3 and 4 where we discuss this in more detail.
 

Jak Angelescu

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Pitch wise yeah, that is the note, as Jak said.

However, when it comes to guitar music sheets, the A string 3rd fret C is considered the middle C note.

This has to do with the fact that guitar sheets only really use the G clef on their staffs. And in in order to still be able to read them sheets without drowning in leger lines, this convention was put in place.

You can take a look at lessons 3 and 4 where we discuss this in more detail.
Andrei I'm confused. Is middle C on piano represented as the C with one ledger line below the staff? I thought it was the one octave higher?I'm not a pianist so I'm honestly asking. If it is, then yes you are right and i was wrong.
 

Andrei Moraru

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Andrei I'm confused. Is middle C on piano represented as the C with one ledger line below the staff? I thought it was the one octave higher?I'm not a pianist so I'm honestly asking. If it is, then yes you are right and i was wrong.
Yes, that is the Middle C note on the piano.

This is the pitch/ height of the note:
. Or this, but you have to pay attention to the microsecond the piano note is played:

As you can see, should you want to play the note with the exact same pitch/height on guitar, it's the B string 1st fret note.

However, when you are reading guitar sheet music and you see the middle C note, you have to play the A string 3rd fret note, which is this one:
.

The idea is that we are both right, but in different ways :). It took me a while to figure it out and wrap my head around it. But if you have a guitar writing software like Guitar Pro, open it up and check for yourself. When you place a note on the A string 3rd fret, you'll see that on the sheet equivalent it's going to be represented as middle C.