The Harmonic Spectrum Set is a full middle octave of 8 tuning forks (C,D,E,F,G,A,B,C) based on the Pythagorean Scale, also known as the Just Scale. The octave of tuning forks in this set is C through the next higher C. They are the traditional chakra frequencies from the Hindu tradition with C being the root chakra, D the sacral chakra, etc. The Harmonic Spectrum Set works at a more physical level than the Chakra Tuning Forks. The Chakra Tuning Forks are not based on a musical scale, but based on the rotation of the planets around the Sun. The Harmonic Spectrum Set is tuned to be more in touch with the physical plane of existence. The physical plane is denser, more crystallized, more cognitive, more centered more around the 5 human senses and the bodily tissues, fluids, bones, organs, etc. In comparison, the Chakra Tuning Forks work more on the cosmic multi-dimensions of our chakras, our subtle bodies and other energy gateways & pathways. You can also tone 2 of the Harmonic Spectrum Set forks together to create a harmonic. The Sharps Set are the sharps of the Harmonic Spectrum Set, so together with the Sharps Set, you have a complete octave in the Just Scale. The Harmonic Spectrum Set emanates pure sounds and overtones to help you relax and center yourself. The process of harmonic repatterning uses two forks together creating various musical intervals. Each interval creates a unique relationship between the chakras and subtle bodies of your energy field. With an understanding of the chakras, subtle bodies, or Polarity Therapy's five element theory of Ether, Air, Fire, Water and Earth, you can creatively combine your intervals to provide a treatment experience with sound. The 8 Harmonic Spectrum Forks plus the 5 Sharps Set make a complete octave in the Pythagorean Scale, also known as the Just Scale. Root Red- C 256 Hz Sacral Orange- D 288 Hz Solar Plexus Yellow - E 320 Hz Heart Green - F 341.3 Hz Throat Blue - G 384 Hz 3rd Eye Indigo - A 426.7 Hz Crown Violet - B 480 Hz Higher octave of Root Red - C 512 Hz Packing in blue velvet bag