Multiphonics

For light finger pressures at particular points on the fingerboard, two or more harmonics can sound simultaneously in a multiphonic. The mixing of two or more harmonics is possible by placing the finger with light pressure between two closely located harmonics. The general effect of producing more than one pitch simultaneously is easily attained and, with practice, specific pitch outcomes can become quite reliable. Since various definitions exist for the term multiphonic, I would define it as the simultaneous sounding of two or more harmonics on a single string.

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