As described in Carl Johan Calleman's book, "The Mayan Calendar and the Transformation of Consciousness", the Mayan calendar consists of nine embedded cycles or Underworlds, all ending on the same date. Each cycle is subdivided into 13 equal intervals or Heavens, and is embedded in the last interval of the previous cycle. Thus, the lengths of the cycles decrease exponentially from one to the next. The cycles are measured in units of tuns, which consist of 360 days.
The following is a brief description of an audio sequence that models the embedded nature of the nine Underworlds. Each Underworld is defined by a chord combination. The component frequencies and the chord durations change exponentially to model the Underworld durations. The longest Underworld is represented by a single 287 Hz tone with a duration of 2000 msec. The next Underworld is represented by the existing tone plus the addition of a second 373 Hz tone. Tones of successively shorter durations are added at times corresponding to the length of each Underworld. The last Underworld is represented by a chord of nine components with a duration of 126 msec. Table 1 shows the frequency and duration of the tone added to represent each Underworld.
| Underworld | Tuns per Heaven | Time per Heaven | Audio Frequency (Hz) | Audio Duration (msec) |
|---|---|---|---|---|
| Universal | 20 days | 2340 | 126 | |
| Galactic | 1 | 360 days | 1800 | 178 |
| Planetary | 20 | 19.7 yr | 1385 | 252 |
| National | 202 | 394 yr | 1065 | 356 |
| Regional | 203 | 7900 yr | 819 | 502 |
| Tribal | 204 | 158,000 yr | 630 | 710 |
| Familial | 205 | 3.15 x 108 yr | 485 | 1002 |
| Mammalian | 206 | 6.31 x 108 yr | 373 | 1416 |
| Cellular | 207 | 1.2 x 1011 yr | 287 | 2000 |
Press play to hear an audio representation of the nine Underworlds. Note that the chord durations do not accurately represent the relative Underworld durations. A correct representation would require very long intervals for the longer Underworlds. For the shortest chord to have a duration of 100 msec, the entire audio sequence would need to be about 73 years long. However, the presented audio does give a feeling for the changes in relative durations, and shows how each underworld is embedded in the ends of all previous Underworlds.