I Love Guitar
Music theory is the method of analyzing our musical system & describing relationships between tones. The true outcome of this theoretical system is the naming of everything (tones, relationships, chords, etc.), & relational description (how each thing relates to another).
The accepted traditional music theory of today is but one of many approaches to explain, describe, & name our musical system.
There are 12 tones in our Western musical system. There could be more, there could be less, but in Western music, the use of 12 tones is the given. We are given 12 tones to create music with. A tone can also be called a pitch. Pitch is the relative highness or lowness of a tone.
This 12 tone system is called Equal Temperament (equally spaced half steps). Just Intonation is another system of tuning based on the pure vibrations of nature (where the harmonics of a given tone are the basis of the tuning - only that key is in 'perfect' tune).
Other systems use 5 tones & this can be called Pentatonic [5 - tones]. Some cultures even use quarter tones, thus each of the 12 tones could be subdivided further. There are also 19 note guitars. For these instruments, what we call the 12th fret, where the tones start over again, is actually the 19 fret. These instruments make some truly interesting sounds, even bordering on bizarre.
Some instruments don't divide the octave [same tone twice higher or lower] into all 12 tones. A mountain dulcimer is a good example, yet some manufacturers do make dulcimers with all 12 tones present [12 frets in the space of the octave].
An octave is a frequency doubling or halving. It's the same tone [same letter name & center point] twice higher or lower.
Frequency is cycles per second [measured in Hertz - Hz] of a pitch. Higher frequencies produce higher pitches, while slower frequencies produce lower pitches. Again, pitch is the relative highness or lowness of a sounded tone.
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