SOUNDS AND NOTES
For first, it’s important to understand what we mean with sounds and notes… Notes are just representing sounds at a specific frequency: human being felt the need to sort different audible frequencies with name of the notes, exactly as he did by giving names to the streets.
But can one sound be considered as music? No, but one sound related to another sound becomes music: music is not to be found within single notes, but in the relationship they form, when a group of them interacts.
The music we know is based on the tempered system, which determines the semitone as the minimum distance between two notes, while two semitones determine the distance of one tone.
The tempered system defines a division of the frequency spectrum in octaves, where every octave is made of 7 notes and 5 alterations, for a total of 12 semitones.
Notes in the tempered system are called C D E F G A B. In the piano, one octave is made by 7 white piano keys (notes) and 5 black keys (alterations). Putting an alteration symbol to a note determines the shift of it one semitone up or down, depending on the symbol we use: with # (sharp sign)the note is shifted one semitone up, with b (flat sign) it’s shifted one semitone down.
Every key is distant one semitone from the adiacent one: for example, as said before there is a semitone between D and D#, one semitone between D# and E and the same between E and F. Notes like D# and Eb are called enharmonics: by executing this two notes with a piano, you get the same sound. It’ s just a matter of perspective, as for us is the same: in relation with your mother you are son, but in relation with a public you’re a performer… in the same way, C# and Db are different way to call the same sound. Piano is the only instrument in music able to reproduce all the notes of the tempered system: in a piano there are 88 keys, for a total of 7 complete octaves and two partial ones at the sides. The octaves are numbered from 0 to 8., so for example C2 is the C key of the second octave of the piano. SCALES A scale is a set of notes selected by a specific sequence. For instance, all the notes connected by one semitone create the chromatic scale. If these notes are played at a distance of: T T sT T T T sT we obtain the major diatonic scale, while if these have the following distance: T sT T T sT T T we obtain the minor diatonic scale. The eight notes of the scale are called degrees and every degree got a different name. KEYS The key is the relationship between a specific sequence of notes and the 1st degree (tonic), intended as the sound where all the other notes of the sequence gravitate around. When we say that a song is written in a specific key, we mean that all the notes used in the composition belong to that specific scale. If during the live performance of a song, because of a mistake some notes out of scale are played, they will generally sound not pleasant to the audience: we say notes out of scale are dissonant.
• Major key is a relationship of notes determined by the intervals seen before as the diatonic scale:
T T ST T T T ST
• Minor key is the relationship of notes determined by the following intervals:
T ST T T ST T T
Minor and major keys of the same note are connected: lowering down of b alteration the 3rd 6th and 7th degree of the major key we obtain the minor key.