In the previous part we had an introduction to what music is and how our brain searches for patterns to understand it. In this second part we start to explore in more details all the rules that allow musicians to create these patterns.
Rules to define all sorts of patterns in music
As defined at the beginning of the canonical definition of music, it is an organized form of acoustic noise and the organization of music works pretty much as Chinese boxes (where each smaller box is contained in a bigger one). Boxes in music are defined by patterns (as already mentioned: melodic, rhythmic and harmonic patterns) and these patterns can be combined and used to build up more complex patterns and structures…
Music patterns are described by music rules and music rules starts from very simple rules (for example, what a music note is) and add other rules over them and so on till becoming capable of organizing really complex forms of music like Symphonic music, jazz music or even atonal music etc…
From a pulse to a rhythm
To understand this principle let’s define what’s a pulse (which may correspond to the heartbeat we mentioned in part 1), a pulse is simply a sequence of unaccented and undifferentiated beats separated by equal units of time. A rhythm is a “pulse with extra rules” that allow a rhythm to describe a more complex pattern, these extra rules may comprehend syncopation or rubato and most of all accents (accents are expressed with an alteration into the dynamics of the sound, so a stronger dynamic or a weaker one also called, respectively, forte and piano).
Our brain is so good to understand rhythmic patterns that it is even possible to create rhythms with every sound (not just sounds emitted by typical music instruments) some excellent examples of this in music production are the beginning of “Age of Shadows” from Ayreon (where mechanical noises are used in an organized form to create a rhythm) or the really famous “Money” from Pink Floyd where cash-register sounds are used to create a pattern with the bass guitar notes…
Rhythm (as well as pulse) has another important characteristic: Tempo. Tempo, in music, is usually the amount of time between each event, where an event is a note or a beat of the rhythm.
Every sound is a pitch… (definition of pitch in music)
Every sound is a pitch, but pitches used in music are organized pitches (again this means that pitches identification follows a pattern which we classified into what’s called chromatic scale) with well-known frequencies (frequencies are measured in Hz – Hertz). Many would be surprised, for example, to know that actually the real difference between the piano note C2 (also known as Deep C) and the note C3 (also known as low C) is that the frequency of C3 is exactly DOUBLE the frequency of C2 (in Western Music C2 frequency is 65.4064 Hz while C3 frequency is 130.813 Hz).
So, while we called them both C, they effectively are different pitches, so note names are used to identify frequency intervals (that determines all the valid notes into the chromatic scale) more than the specific frequency of a pitch (specific frequency of a pitch requires an additional name or identification number as it happen for C2 and C3 examples). In simple words, C alone may mean a pitch at: 32.7032 Hz, 65.4064 Hz, 130.813 Hz and so on…
A musical note is not just a single frequency, in fact a musical note is usually composed by different elements we can classify as attack, body and tail. It’s really important to understand this concept in order to learn individual music instruments properties and their orchestration (to correctly decide which parts each instrument should play in a song).
A musical note, as we can hear it from almost any musical instrument, is also composed by what’s called harmonics, so the frequency, the attack, body and tail of a note are generally surrounded by extra frequencies.
These harmonics on acoustic instruments are extra upper frequencies relatives to the note we want to play, these extra upper frequencies are integer multiplier frequencies of the frequency of the note we are playing. So if we use again the example of C3 (“Do 3” in the original Italian music terminology) we’ll have the following harmonics:
1st Harmonic -> 130.813 Hz -> fundamental tone (our C3 note frequency)
2nd Harmonic -> 261.626 Hz -> 1st overtone (which correspond to C4 note frequency! Also known as Middle C)
3rd Harmonic -> 392.439 Hz -> 2nd overtone (this is a bit complicated, but anyway, this frequency is almost a G4. G4 note frequency, in western music, is 391.995 Hz, so our ears would not hear any difference between C3 2nd overtone and G4)
4th Harmonic -> 523.252 Hz -> 3rd overtone (this is a C5 or Tenor C)
From the schema above we understand that all harmonics of a given note belong to what is known as Major scale relative to the note we are playing and that the term overtone applies from the 2nd harmonic on.
So, a real world music note is actually a set of acoustic frequencies (attack, fundamental note + harmonics) that behaves according to the mechanics of an acoustic instrument and (for string based instruments) to the touch of the musician (attack, body and tail).
Some extra info about attack and tail:
Each instrument has a specific type of attack (for example, piano sound has a percussive attack given the mechanics of the piano instrument, guitars have a more picked) as well as a “fading effect” of the note tail given by the fact that the piano string will slowly cut its vibrations causing that fading effect.
Please note: for what concerns Synthesizers their notes actually behave as the user “programmed” them to behave (but again there is an attack, a body and a tail, while there maybe not harmonics or overtones depending on the way the user programmed the synth or there may be extra layers of sounds/samples making the note set of frequencies even more complex than an acoustic instrument).
All this information about how instruments produce notes we hear in songs is very important because it lets us understand why each instrument has a different sound than the others even when playing the same note. In other words a C4 played on an electric guitar will sound different from a C4 played on a Cello or on a Piano and their specific sound can help to express different moods.
A note is just the beginning of all the patterns in music…
A small sequence of notes is usually called “musical phrase” (or musical sentence). These small sequences of notes are grouped together and called phrases (or sentences) because they have a “musical sense” on their own.
A musical sense is nothing more than a pattern of notes understandable for our brain. For example, a sequence of adjacent notes that are distributed following fragments of musical scales can make much more sense for our brain than a random sequence of notes.
There are a number of techniques used to write musical phrases that we will discuss in detail in future articles.
A musical phrase can be classified as a “question” or as an “answer“. In tonal music, usually, the difference between a musical question phrase and an answer is that the answer often tends to end on the root note of the scale at the base of the two phrases while the question phrase tends to end on a different degree of that very same scale.
Some extra info about musical phrases:
Ending a phrase on the root note gives the sensation of completeness while ending a phrase on different degrees of a scale creates that suspension feeling that should be resolved somehow. So writing question and answer phrases that way also gives the effect of “complementarity” that the two phrases usually present.
A combination of multiple musical phrases and rhythm is called melody. A melody is always perceived by a listener as a complete entity and usually it is the part of a song where listeners start to make associations with moods, emotions and mind states of the song.
A musical Riff is a well-defined melody that can also present harmonies.
Harmony is the 3rd of the macro-components of music and we’ll have a deeper look at it on the next part of this article. Harmony also helps a lot to express moods, emotions and mind states in music.
Hope you enjoyed this long 2nd part and I’ll see you on the next one!