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-- == Rhythm --==
-- == Harmony --==
-- == Melody --==
-- == Timbre --==
-- == Applied to Guitar --==
-- == Do Re Mi Fa So La Ti Do --==
-- == The Chromatic Scale --==
-- == Semi-tones and Whole-tones --==
-- == Sharps and Flats --==
-- == The Major Scale --==
-- == Analysis of the Major Scale --==
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Music is based upon 4 main properties of sound: rhythm, harmony, melody, and timbre. It is impossible to isolate any one element in a complete vacuum.
Rhythm is a pattern of sound over time. This can be a single note sustained infinitely, a drum beat, dynamic accents in a melody, etc. The vast majority of compositions seek to establish some sense of order in rhythm. Thus, most songs are locked to a specific tempo and time signature. Tempo establishes how many regular intervals of time (or beats) should occur within a certain period of time, usually a minute. A common tempo is 120 beats per minute (bpm). This means there are 120 equal intervals of time per minute. Each beat will contain the standard minumum of controlled sound. For example, a drummer may play one stroke per beat, or a guitarist may strum a chord once per beat. Of course, doing the same thing every beat is boring. Master musicians know how to play "around" the beat, "off-beat", across several beats, or even subdivide a beat. But the point is that tempo provides a framework in time to create order - the listener does not feel lost, and a band or orchestra consisting of numerous instruments can simultize their playing to create a unified whole.
Now 3/4 - boom ssss taah boom ssss taah.
Harmony is the pattern of how frequencies interact. Most natural sounds are relatively noisy - they contain a random selection of frequencies. The true definition of noise is sound with equal distribution of all audible frequencies. Consider an untuned radio or TV, which produces white noise - you cannot "zero-in" on any particular frequency, although your brain may try. Noise is chaos, and all true noise is undifferentiatable from other true noise, regardless of its source. Conversely, a pure frequency is represented by a sine wave. Again, this is more easily understood by our minds - we can recognize it easily and even recreate it vocally. But of course it is boring. Popular instruments do not create a pure, single frequency, but a multitude of frequencies (and noise). This is discussed further in timbre below. But most instruments are designed to create notes, which are based around a fundamental frequency. This frequency is the most prominent and recognizable. Harmony is concerned mostly with the interaction of these fundamental frequencies.
Another topic for the composer is arrangement. Arrangement describes applying some musical idea into a selection of instruments. For example, if you were arranging a piece for flute, piano, and bass, you would likely have the flute play the melody, the piano playing chords, and the bass usually playing the root note of the chords. Naturally, melody is usually given a higher-pitch than the other instruments, and the root note of chords is usually played in the lowest-frequencies. We could come up with different arrangements that are harmonically equivalent; however, they would likely be less enjoyable to listen to.
Melody is very similar to harmony, but more concerned with sequences of single notes over time than with the combination of multiple notes. Again, it is very difficult to conceptualize harmony and melody as completely separate entities. Melody are the lines to our favorite songs we sing - a melody can tend in a particular direction, finding resolution, having accents. It doesn't require harmony, although harmony often gives it its context.
Again, melody can get insanely complex...so what's our simple framework. Really, it's the same frameworks as harmony and rhythm. We take a subset of all possible frequencies and give them note names, and restrict them to 12 possibilities, with only 7 being "active" for a particular key or scale. Note duration is restricted to common set, based around beats. The big divergence from harmony is that pitch between octaves has signfigance. So, for example, if we take a common A minor ascending scale starting at A2 (110 HZ) as our melody; our last note should be A3 (220 HZ). Here is the example melody: A2, B2, C3, D3, E3, F3, G3, A3. This makes sure each note has an ascending pitch compared to the prior note's pitch. Similarly, A2, B3, C4, D5, E6, F7, G8, A9 is not the same melody, despite having all the same note names. It will sound much different to the listener.
Timbre is the quality of a particular sound. It is why a horn sounds like a horn and a violin a violin. Musical instruments tend to focus on sounding particular frequencies, but not necessarily. For example, drums are not designed to focus as much on frequency as the general sound they create. Some instruments are noisier than others. Some have more overtones than others. Some can have a soft attack or even swell slowly louder until at full volume, while others might have a very noticeable, percussive attack. Some may sustain forever (synth). Some may decay immediately (sitar).
Timbre factors mainly into arrangement choices than fundamental composition; however, at some level, composition is determined by timbre, and timbre determines what we actually hear and how it is percieved. For example, a melody designed for flute cannot be played on drums, and a drum beat cannot be played on flute. It may technically be possible, but it will lose its meaning. Similarly, each instrument has a range. A composer desiring the use of a certain instrument for a certain part will compose that part within the range of the instrument.
Guitar is such a popular instrument because of its extreme versatility. It can be percussive and rhythmic (funk playing). It can play rich harmonies. It has a large range, able to play most melodies. There are a wide range of techniques to embellish traditional playing. The angle you hold the pick and where you pick the strings can affect the tone. The type of pick you use. Finger picking. And then there are loads of different effects, such as compression, volume pedals, wah pedals, distortion, delay, reverb, modulation, pitch shifting, and synth filters, that expand even further upon this. Guitar fits into band contexts as well as being sufficient for solo compositions.
We all know the sound of the common major scale: Do Re Mi Fa So La Ti Do. Really it's like a short little melody. But where did it come from? Why are the frequencies chosen what they are? These are really, really big questions. It involves some serious music history, psychoacoustics, math, and conscious design. I feel they are important to answer, but it's still too early. For now, we need to understand simply that it works. If we sing Do Re Mi Fa So La Ti, we feel the tension. Where's that final Do? Similarly, if we just sing Do Re Mi, we want to keep going to the Fa; then it feels ok to end. The tension is at least partially resolved. We can also end on the So.
In our scale, Do is unison or octave, a 1:1 or 2:1 ratio with our root or tonic note. Fa and So are the 4th and 5th intervals with the tonic note - the most harmonic intervals other than the octave.
The chromatic scale, or 12 tone scale, is basically made by dividing an octave into 13 equal pieces (on a logarithmic scale). Each dividing point is a note on the scale. Since the octave note already occurs as the root note, we are left with 12 distinct note values (A, A#, B, C, C#, D, D#, E, F, F#, G, G#). Notice that there is no B# or E#. This has nothing to do with frequency - it is a convention in note naming. E - F spans the same frequency range as A - A#.
The "distance" from one note to the next in the chromatic scale is called a semi-tone. So A - A# or E - F is one semi-tone. A whole-tone is 2 semi-tones. So A - B is a whole-tone, just as A - A# and A3 - B are two semi-tones.
Sometimes whole-tones are called whole steps and semi-tones are called half steps.
'#' means "sharp". 'b' means "flat". These terms indicate the named note is raised or lowered one semi-tone. Multiple sharps and flats can be used. For example, Abb is 2 semi-tones below A. Abb corresponds to the same frequency as G. Similarly, G# is the same frequency as Ab, and B# is the same frequency as C. For our purposes, we are unlikely to ever deal with double (or more) sharps or flats. But it's important to understand what they are to remove some of the mystique from them.
The major scale is composed of 2 whole-tones, a semi-tone, 3 whole-tones, and a semi-tone. Below is the chromatic scale starting on C, then the C Major scale. The s's represent semi-tones and the w's represent whole-tones. The chromatic scale consists of 12 semi-tones.
A B C# D E F# G# A
Notice how the major scale is really just a whole, whole, semi sequence, then a single whole tone, then another whole, whole, semi sequence. (w w s) w (w w s). The (w w s) sequence is called a tetrachord (actually has 4 notes), and is historically very important in the development of music. It is our Do Re Mi Fa melody from above.