Musical Connections

Call this one a rabbit hole.  It's interesting, but still just a rabbit hole.

There are 10 octaves in the range of human hearing, which is 20hz to 20khz It doesnt go back to zero, just goes higher than humans can hear. There are 24 lines in the poem, or 2 octaves.

Maqam

Arabic maqams are based on a musical scale of 7 notes that repeats at the octave. Some maqams have 2 or more alternative scales (e.g. Rast, Nahawand and Hijaz). Maqam scales in traditional Arabic music are microtonal, not based on a twelve-tone equal-tempered musical tuning system, as is the case in modern Western music. Most maqam scales include a perfect fifth or a perfect fourth (or both), and all octaves are perfect. The remaining notes in a maqam scale may or may not exactly land on semitones. For this reason maqam scales are mostly taught orally, and by extensive listening to the traditional Arabic music repertoire.

Since microtonal intervals are impractical to accurately notate, a simplified musical notation system was adopted in Arabic music at the turn of the 20th century. Starting with a chromatic scale, the Arabic scale is divided into 24 equal quarter tones, where a quarter tone equals half a semitone in a 12 tone equal-tempered scale. In this notation system all notes in a maqam scale are rounded to the nearest quarter tone.

The 24-tone system is entirely a notational convention and does not affect the actual precise intonation of the notes performed. Practicing Arab musicians, while using the nomenclature of the 24-tone system (half-flats and half-sharps), still perform the finer microtonal details which have been passed down through oral tradition.

Maqam scales that do not include quarter tones (e.g. Nahawand, ‘Ajam) can be performed on equal-tempered instruments such as the piano, however such instruments cannot faithfully reproduce the microtonal details of the maqam scale. Maqam scales can be faithfully performed either on fretless instruments (e.g. the oud or the violin), or on instruments that allow a sufficient degree of tunability and microtonal control (e.g. the nay or the qanun, or the Clarinet). On fretted instruments with steel strings, microtonal control can be achieved by string bending, as when playing blues.

The exact intonation of every maqam scale changes with the historical period, as well as the geographical region (as is the case with linguistic accents, for example). For this reason, and because it is not common to notate precisely and accurately microtonal variations from a twelve-tone equal tempered scale, maqam scales are, in practice, learned auditorally.

The central tones (nucleus) of a maqam are created from two different intervals. The eleven central tones of the maqam used in the phase sequence example above may be reduced to three which make up the "nucleus" of the maqam.

There are nine maqam families:

Ajam
Segah
Bayātī
C minor
Rast Panjgah (means right or direct)
Hijaz, aka Phrygian Dominant Scale (aka "Spanish gypsy scale")
Saba
Kurd
Nawa Athar (aka "Hungarian Gypsy Scale")

Indulgence

Indulgence anagrams to "ending clue".

The end is the beginning, the beginning is the end.

We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time. 
T. S. Eliot

The last clue is also the first clue, is also the ending, but also the beginning.