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“When a Shamanic Drum is struck upon one side, it produces the sound of the beat, and a primary tone, or resonance. Since the hides covering the two sides of the drum are never able to be strung to precisely the same tautness, one side will always have a slightly higher pitch than the other side. The primary tone on the higher-pitched side will, consequently, have a "ring" to it. When the lower-pitched side is struck, a lower "tone" is produced in addition to the beat. Because of the close proximity of the hides to each other, being only 7 to 9 cm apart, when one side of the drum is struck, the sound wave of that strike impacts the other side's hide, causing it to resonate as well. We now have three tones being produced simultaneously from one strike: the beat, the primary tone (either a "ring" or a "tone," depending on which side is struck) and the secondary resonance of the opposing hide's vibration.”
Excerpt from Shamanic Journey Part 1 by  © 2018 Written by WolfEye Dances with Dolphins | Freja Enjoy Hjälmbåge.