Music is mysterious stuff. It’s completely invisible. You can’t smell it, taste it or feel it in a normal sense, yet it can touch you. Fair enough you can hear it, but what makes music different from anything else you may hear? After all, it uses the same parts of your body you would use to detect a barking dog, or an engine starting. We have evolved ears as a kind of early warning system for our eyes - We will hear a bus coming before we see it, so we’re less likely to get run over by it. Music was not ‘planned’ by nature, and has no real purpose in our survival except for what we have made of it since we discovered it.
It’s a concept which has been invented by humans, and only humans can really appreciate it. Your dog may associate the theme tune of EastEnders with dinner-time, or be trained to jump about when a particular song is played but it will not really enjoy music the way we do.
Music is therefore a somewhat magical, even spiritual experience that is gone as soon as it ends and leaves no trace. But whilst it’s there, it can convey feelings of joy, pain, anger, excitement, love, hate, contentment or longing. It can give us images in our minds of beautiful landscapes, terrible storms, war, peace, wide open spaces or claustrophobia. Some music can make us sit down and close our eyes, whilst other music can make us dance like we’ve lost our minds, in a nightclub at 3 a.m.
All this just because the air in the room is vibrating a bit?
How can something so mundane as this be the basis of thousands of years of culture? Why does music stir the soul, yet, all that is happening physically is changing air pressure? Why does it sound so simple to the ear, yet look so mind-bogglingly complicated on paper? These are some of the questions I hope to answer, and hopefully I can draw a link between what happens in the air, and what happens in our minds.
Building Blocks.
I will start with a pretty much ‘text book’ definiton of music:
Most music, no matter how varied will follow simple rules. It will have a melody, some harmony and some rhythm.
A melody is defined as ‘a string of notes, one after the other’. Melodies are the part of a tune that you will remember easiest. When you sing along to a song, you usually sing the melody.
Many melodies and most music is based on scales.
A scale determines which notes are used to play (or write) a tune. Scales (on their own) are played in order from low through to high. The Major scale sounds like the tune ‘Do, Re, Mi, Fa, So, La, Te, Do.’
The simplest scale to understand and recognise would be C Major because there are no black notes (sharps or flats) in it, and I will use it throughout this article to demonstrate several things.
Harmony is defined as ‘When other notes are played at the same time as a melody to make the tune sound more interesting, or to give it texture.’ Harmony can take the form of either chords - long held notes that sound nice with the melody:
or counterpoint - a second melody which complements the first, (sometimes called a counter-melody):
More than likely, a piece of music will be in a key which means that all the notes played in a particular tune will have some relationship with the note the key is named after. ‘Twinkle Twinkle’ is in the key of C and uses the major scale so we say it is written in C Major.
Nine times out of ten, the first and last chords in a piece of music will indicate it’s key and scale.
Rhythm is the beat or pulse of a song. Any note you play can be broken down into lots of different lengths and then arranged into a seemingly infinite number of rhythms. In standard notation, we give each note length a name. Each new name is half the length of the last. They are called ‘breves’, ‘semibreves’, ‘minims’, ‘crotchets’, ‘quavers’, ‘semiquavers’, ‘demi-semiquavers’ and ‘hemi-demi-semiquavers’!
There are also times when you may wish to use unusual, non-standard note lengths in part of a melody. These are called tuplets and do not follow the normal 1 - 2 - 4 - 8 - 16 pattern. Triplets (3 notes in the same time as 4) and sextuplets (6 notes in the same time as 8 ) are the most common tuplets, but even stranger numbers of notes, for instance 5 (quintuplets) or 7 (septuplets) are possible although these are not very common. All tuplets are indicated by a curved line with a number inside representing the value of the tuplet.
As you can imagine, there is an unlimited amount of note combinations, harmonies and rhythms available, as well as all the thousands of different instruments you can use to play them. This is what makes music so varied and so interesting, but so far, we have only described how the building blocks fit together and a little bit on how music is written down. We haven’t even scratched the surface of how it works.
Like the ancient Greeks looking at the world, realising that there must be fundamental constituants in nature and predicting that atoms exist, we too have to strip down music even further and ask -
But what are the building blocks made of?
And how do they relate to each other? We must break music down into its simplest parts and work back up. What we will find is that the three key ingredients; Melody, Harmony and Rhythm are all really one and the same thing.
Tuning Up!
Sound is made of pressure waves. When a loudspeaker’s cone moves forwards, it pushes the air directly in front of it forwards with it and the air pressure increases. You will probably have experienced this if you have ever put your hand in front of a speaker when the stereo is turned up high. When the speaker moves backwards, the air pressure drops to below normal. The bigger the change in pressure, the louder the sound will be. The faster the cone is vibrating, the higher the pitch of the sound will be.
Sound travels through the air because each air molecule will pass its energy on to its neighbour like in a microscopic 3D game of snooker.
If you had a very special video camera and took a molecular snapshot of the room you would see that there are waves of high and low pressure coming from the speaker at around 330 metres per second, which is the speed of sound in air.
These areas of high and low pressure can be plotted on a graph which we call a waveform this is the graphical representation of air-pressure (vertical axis) over time (horizontal axis) and is the most common visual representation of sound. The highest part of the wave is called a peak and the lowest part is called a trough
Music is different from any other sound you may hear. Firstly because it is made of tones. A tone is what is heard when a sound’s waveform repeats itself regularly and smoothly. This is heard as a pleasant sound because your brain interprets it as a regular, predictable pattern. Also, because the sound is regular, only a small part of the workings of the ear will be sending signals to the brain. The less work the brain has to do to interpret a sound, the purer the tone that is heard. If a sound’s waveform is irregular and chaotic, information coming in to the brain from the ear will also be irregular and chaotic, plus the ear will have information overload and will have to work harder, it will therefore not be interpreted as a regular pattern and you will hear a noise.
Most sounds you will ever hear are noise. Maybe this is why when something as pure and regular as a tone is heard, we suddenly become interested.
When two tones of equal amplitude and frequency are played in unison, there are two extremes which can happen.
If a peak meets another peak (trough meets another trough) they will reinforce each other - i.e. If two loudspeakers move forwards at the same time, the air pressure will be raised by both - the waves are said to be ‘in-phase’.
However, if a peak meets a trough they will cancel each other out and you will hear nothing - i.e. if one loudspeaker moves forward whilst one moves back, the overall pressure will remain unchanged - the waves are said to be ‘out of phase’. These like I said before are the two extremes, and there are of course many results in between the two waves being in and out of phase.
Harmony, as we said earlier, is extremely important in western music. This is because when certain tones are played along with others, they appear to complement each other, sounding pleasant to the ear.
A tone’s frequency (pitch) is measured in cycles per second or Hertz (Hz). The more cycles per second, the higher the note.
If a tone of 100Hz is played at the same time as a tone of 200Hz, you will hear the interval of an octave*.
The sound of an octave is generally a pleasant one because your brain will identify this as a pattern. You will be able to hear both 100Hz and 200Hz transparently as two notes one octave apart. Octaves are the strongest interval and are most pleasing to the ear. The resulting waveform (the two waveforms added together) will also look regular.
*All octaves are exactly twice the number of cycles per second than the original (root) note. i.e. 100Hz … 200Hz … 400Hz … 800Hz …1600Hz etc.
Another way to explain this is by doing a thought experiment (or a real one if you have the equipment). Set up a tape machine to record a metronome. Firstly set the metronome to play at 100 beats per minute and press record. Leave the machine recording for ten minutes or so then press stop. Rewind the tape. Now, play back the tape but as you do this, gradually increase the speed of the tape. The clicks will get faster and faster until your brain can not distinguish between two individual clicks. Instead, you will hear a low tone (anything over about 25 beats per second will be heard as a tone). Once the tape is at a massive 60 times it’s normal speed, the metronome will be ticking at 100 beats per second and you will hear a tone of 100Hz. Metronome One
Next, grab a second metronome and set it to run at 200 beats per minute alongside the first one (ensuring both metronomes start at the same time). Start recording, again for about 10 minutes. On playback at 60x speed, you will not hear two metronomes clicking but two notes, one octave apart! Metronome Two Take a few seconds to think about this…
Now what happens if you get a third metronome and set it to 300 beats per minute then repeat the process? You may expect another higher octave on playback, but, this is where it gets really strange…
As you can see from ‘Metronome 2’ clicks twice as fast as ‘Metronome 1’. This gives us the octave when sped up. However, metronome 3 is only one and a half times as fast as ‘Metronome 2’ (three times as fast as ‘Metronome 1’). When sped up, the resulting sound will be the harmony of an octave plus a fifth! Or a C*, a C an octave above and the G above that. Metronome Three
CCG* The frequency of C and it’s octaves are not really 100Hz and 200Hz but 131Hz and 262Hz respectively, but I will use it to demonstrate, as it’s easier to visualise.
It is called a fifth because it is five notes away from the root note when using the major scale. Likewise, a third is three notes from the root, and an octave is eight notes away.
A metronome running 4 times faster that ‘Metronome 1’ will give us our next octave (or next C) simply because it is clicking exactly four times as fast as ‘Metronome 1’ and exactly twice that of ‘Metronome 2’. An octave is always double the frequency of the original tone. A fifth of this octave is always one and a half times the frequency of the octave or three times the original frequency. We say that this interval has a ratio of 3:2 because there exactly 3Hz coming from one tone for every 2Hz from the other. 3 ÷ 2 = 1.5 so we can use the value of 1.5 to work out the fifth note of any frequency.
If you had not noticed, I have just shown how rhythm and harmony are intrinsically related. Tones, harmony and ultimately melody are really just super-fast perfect rhythms. Had the metronomes been clicking randomly and out of time with each other, the resulting sound upon high-speed playback would have been noise.
If we carry on this process with more and more metronomes we will eventually construct what is known as the Harmonic Series.
The harmonic series of a particular tone is worked out by playing multiples of its frequency. Fifths are the next strongest interval after octaves. This is because a fifth is the first new note in the harmonic series. When C and G are played together, the resulting harmony is strong or Consonant - however if a C and a C# are played together it would not sound particularly nice. This is said to be Dissonant.
If the original frequency is 100Hz then:
1×100=100Hz (Original tone) - Root note
2×100=200Hz (First Harmonic) - Octave
3×100=300Hz (Second Harmonic) - Fifth
4×100=400Hz (Third Harmonic) - Octave
5×100=500Hz (Fourth Harmonic) - Third Metronome Five
etc
If you carry on the pattern you will find the natural harmonic series of C…
This as you can see ends up very high before too long and because these tones are natural harmonics and not notes based on a western scale, the actual sound of the latter ones will start to sound ‘out of tune’. The F for example will not sound like a convensional F on a keyboard, but rather in between an F and an F#. This is not a mistake, it’s the way it works in nature. When we started to learn about the harmonic series and build instruments like harpsicords and pianos where all the notes were present on one keyboard, we had to average all the frequencies out to make all notes sound relatively pleasant together and to allow us to play songs in different keys without them sounding wrong. The traditional 12 note scale used on very early pianos was called a “Just Scale” and it means that the F is slightly flattened along with other notes to make it sound correct.
This made all scales work in all keys and our ears simply became used to it. The Just Scale was used for a very long time and the modern ‘Equal Temperament Scale’ isn’t a million miles away from it.
In eastern scales however, there are between 5 and 22 notes, each note different and having different names, but in the east, melody and rhythm are much more important than harmony. Strangely, our dense western harmonies often sound horrible and cluttered to eastern ears.
NEXT TIME…
Circle of Fifths /Just Scales / Equal Temperament Scales / Naming Chords and Modes and much more!!!
Any questions on this article, please get it touch!
more articles by James Mulvale
- Killer Finger Exercises 1
- Get your licks and riffs up to speed!
- Home Recording Techniques Part II
- More Music Stationary (Manuscript / SATB / Piano / Strumming Charts)
- Blank Stationary for Guitar / Bass / Mandolin / Banjo
- Home Recording Techniques part I (Setup/Sequencers/MIDI basics)
