Note the notched mouthpieces of the 2 outer flutes top left; these mouthpieces were discovered in the collection of West Mexican prehispanic flutes at the University of Wales, Bangor. The notch adds a subtle high whistle sound to most of the lower primary tones, and sounds somewhat as if a quiet ghost is playing along. The top larger flute has 4 finger-holes and a beautiful quiet tone; it ends in a small cone that lowers the fundamental, and depending on its construction, can alter the flute's timbre slightly; I am still researching this property. The small cone on 2 flute's end tubes were also discovered on flutes in the W. Mexican collection. The flute with a blue band in the middle also ends in a small cone; it does not have a notch but does have a slightly altered aperture which affects the timbre of some pitches on this flute with 7 finger-holes, including a thumb hole. The remaining flute with a blue squiggle does not end in a cone; it does have a notched aperture, and has 7 finger-holes.
These 3 flutes are tuned to play together.
These two double flutes can be played separately or together.