We are all aware that an unborn child is capable of hearing. Our sense of hearing begins long before our sense of vision. As such, sound becomes a powerful form of stimulation for achieving desired brainwave states. Sound stimulation can come in many different forms. Some of the most common include: surf or pulsed white noise, pulsed tone, white noise and tone combined, pulsed chord, binaural beats, dual binaural beats and white noise with either binaural beats or dual binaural beats.

Nearly all light and sound instruments are capable of generating white noise. You know that fuzzy sound your television makes when you are between channels? Or the sound rushing water makes as it flows by you? That’s what pulsed white noise sounds like. Pulsed tone is just like white noise except a pitch is utilized. Your light and sound instrument should have the ability to let you adjust the pitch.

Combining pulsed tone to pulsed white noise is often used in “entertainment” sessions for creating special sound effects. A pulsed chord is basically the combination of two pulsed tones that are set apart at musical intervals.

A binaural beat is the combination of two audio frequencies or tones. One tone is directed to the left ear while the other tone is directed to the right ear. Say the left ear is receiving a tone of 180Hz and the right ear is receiving a tone of 190Hz. What the brain actually “hears” is 10Hz, which is the difference between the two and is known as the offset frequency. Dual binaural beats are created simply by combining two totally independent binaural beats. The resulting four channels of audio beats work together to generate several offset frequencies. The resulting frequency variations are very dynamic and complex, and have become the ideal method for maximizing brainwave entrainment. In fact, dual binaural beats are so effective that listeners can utilize stereo speakers rather than headphones and still receive the full effect. White noise is sometimes combined with either binaural beats or dual binaural beats. This method is limited, however, to session designs targeting relaxation and meditative states.

Phase settings for pulsed tone and white noise are connected to the light settings. By combining sound with light, you can utilize eight different phase settings: in phase, out phase, cross phase, sound out phase with lights in phase, sound in phase with
lights out phase, clockwise motion, counterclockwise motion and front/back phase. All phase settings are rather self-explanatory and are described in more detail in the owners manual of your light and sound instrument. Phase settings with dual binaural beats
involves a little math and some experimenting. For information on creating sessions utilizing binaural and dual binaural beats, see “Mind States / An Introduction to Light & Sound Technology” by Michael Landgraf of Mindmachines.com.

Left Channel On / Right Channel On

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Standard In-Phase

Left Channel On / Right Channel Off

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Standard Out-Phase

Left Light On / Right Light Off Left Light Off / Right Light On

Left Sound Off / Right Sound On Left Sound On / Right Sound Off

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Cross Phase Light and Sound Stimulation

Both Light Channels On Both Light Channels On

Left Sound On / Right Sound Off Left Sound Off / Right Sound On

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Sound Alternating with In-Phase Light Stimulation

Left Light On / Right Light Off Left Light Off / Right Light On

Both Sound Channels On Both Sound Channels On

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Sound In-Phase with Alternating Light Stimulation

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Clockwise Light & Sound Stimulation 1=On O=Off

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Counterclockwise Light & Sound Stimulation 1=On O=Off

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Front / Back Light & Sound Stimulation