#### Foreword

The following presentation is for anyone curious about the pitch parameter of music
(pitch and interval comprehension, just intonation, temperament, microtonality, etc.).
It provides background for the
H-System,
which is the basis for Tonal Plexus keyboards and the MegaScore notation.
This presentation is oriented towards seeing and hearing, and requires no
previous experience with music theory. Historical information is included only when it is both relevant and logical, and
some historical facts are simplified for the sake of clarity.
The following basic concepts are assumed to be understood:

- the idea of
*high* and *low* pitches, derived from the untrained human voice
which physically raises and lowers in the throat when producing pitches which we call *higher*
or *lower*
- whole numbers in counting order, as learned at an early age: 1, 2, 3, 4, etc.
- multiplication and division of whole numbers by 2, stated as fractions or ratios; i.e. 2/1 or 1:2
- the first seven letters of the Latin alphabet, in order: ABCDEFG

*This work is dedicated with gratitude and respect to those whose writings have inspired and
influenced mine, most notably
***Harry Partch**
(Genesis of a Music),
**Dr. Martin Vogel**
(On
The Relations of Tone), and
**Dr. Patrick Ozzard-Low**
(21st Century Orchestral Instruments)
**—
Aaron Andrew Hunt**

#### Contents