Multiphonics - Introduction
Introduction
What is a Multiphonic?
A multiphonic is the sounding of multiple pitches from a single source which would usually be considered monophonic in nature. As single string playing is generally monophonic, multiphonics have provided a fresh area of sonic exploration for composers and performers.
There are various ways in which multiphonics can be produced but the sonic result is often essentially similar.
In each case, the lowest pitch will be the fundamental, and a complex series of cluster pitches from its harmonic series will form around it. Depending on various factors, the additional partials may be spread over a wider or lesser pitch range if certain technical procedures such as bow speed or placement are carefully controlled. As the left hand finger is not totally depressed when performing multiphonics, this allows the string to vibrate on both sides of the finger. The reduction in finger pressure required to produce multiphonics produces a unique physical reaction in the string in which a short signal loop on each side of the string is phase locked into the vibration pattern of the fundamental. This results in a multiple sound caused by a series of simultaneous vibration patterns within the same string.
Technical Practice
Left Hand
The left hand technique used in multiphonic production is very similar to producing natural harmonics. The string is very depressed at the given node point using a finger pressure slightly greater than that used for natural harmonics.
The Bow
The bow is subject to a stricter set of parameters than for the production of harmonics.
What is a Multiphonic?
A multiphonic is the sounding of multiple pitches from a single source which would usually be considered monophonic in nature. As single string playing is generally monophonic, multiphonics have provided a fresh area of sonic exploration for composers and performers.
There are various ways in which multiphonics can be produced but the sonic result is often essentially similar.
In each case, the lowest pitch will be the fundamental, and a complex series of cluster pitches from its harmonic series will form around it. Depending on various factors, the additional partials may be spread over a wider or lesser pitch range if certain technical procedures such as bow speed or placement are carefully controlled. As the left hand finger is not totally depressed when performing multiphonics, this allows the string to vibrate on both sides of the finger. The reduction in finger pressure required to produce multiphonics produces a unique physical reaction in the string in which a short signal loop on each side of the string is phase locked into the vibration pattern of the fundamental. This results in a multiple sound caused by a series of simultaneous vibration patterns within the same string.
Technical Practice
Left Hand
The left hand technique used in multiphonic production is very similar to producing natural harmonics. The string is very depressed at the given node point using a finger pressure slightly greater than that used for natural harmonics.
The Bow
The bow is subject to a stricter set of parameters than for the production of harmonics.
- The bow should exert slightly more pressure than usual and should be drawn with a consistent speed which should be slower than for harmonics.
- Careful placement of the bow also allows the multiphonics to speak more effectively. As a general rule, the bow placed on the 9th and 13th partial of the relevant string will prove to be most effective. However, if the bow is placed in the rough vicinity of these partials then the multiphonic will speak.
So for example:
Weight and Pressure
Heavier bows present a challenge; my own experiments have concluded that multiphonics speak more easily with lighter bows and with lesser hair contact. In many cases, the use of a Cello bow (and some case a Violin bow) proved to provide the optimum weight to pressure ratio. However, each instrument will respond differently and the instrumentalist should experiment to find the ideal bow weight and placement for each multiphonic in question
Heavier bows present a challenge; my own experiments have concluded that multiphonics speak more easily with lighter bows and with lesser hair contact. In many cases, the use of a Cello bow (and some case a Violin bow) proved to provide the optimum weight to pressure ratio. However, each instrument will respond differently and the instrumentalist should experiment to find the ideal bow weight and placement for each multiphonic in question
Notation
The typical notation is the same as for harmonics (diamond notehead) with an M or MP above the pitch to identify it as a multiphonic.
Variability
It is important to realise that multiphonics will vary between instruments. Some examples can be found here:
The typical notation is the same as for harmonics (diamond notehead) with an M or MP above the pitch to identify it as a multiphonic.
Variability
It is important to realise that multiphonics will vary between instruments. Some examples can be found here:
Charts
The following multiphonic charts are divided into three sections:
The following multiphonic charts are divided into three sections:
- Simple multiphonics - multiphonics that speak relatively easily.
- Difficult Multiphonics - multiphonics that are more difficult to produce or are unreliable
- Multi Node Point Multiphonics - multiphonics that require more than one node point to be activated.