Classification Reference

NOTE: This is a work-in-progress, an ongoing compilation of ORGANOLOGICAL classifications which have historically been established for the field of ethnomusicology. My goal is to establish a generalized and USEFUL reference system to describe the basic physics of sound for the practice of musical instrument design.

Here is my streamlined reference system pulled from other systems which I included below for your reference. These categories help me conceptualize the basic initial physical and elemental sound producing processes. One of my goals as a new instrument designer, however, is to challenge and complicate these categories by combining and altering these concepts to produce new sounds and musical contexts.

PRIMARY SOUND CLASSIFICATION:

  1. IDEOPHONE: sound is produced by vibrations in the solid three dimensional body of an instrument. examples include gongs, sticks, stones, xylophones, cymbals, claves and other three-dimensional vibrating objects. These objects are free solids with no internal or external tension placed on them.
  2. MEMBRANOPHONE: sound is produced by vibrations in a thin membrane. The membrane is principally two dimensional in the sense that the thickness is small compared with the two dimensions of its surface. The membraned must be have at least one end fixed if not all ends fixed to produce maximum vibrations. For example the drum rim clamps the drum head and stretches it into place. Examples include skin and wood drums, membrane cello, and loudspeakers and gramaphones*.
  3. LAMELAPHONE: sound is produced by vibrations from a solid fixed at only ONE end. examples include music box, kalimba, thumb piano, toy piano, electric piano, and tine organ.
  4. CHORDOPHONE: sound is produced by vibrations from a solid fixed at TWO ends such as string, wire, elastic, rubber tube, and silicon string as well as springs and 2 dimensional bands or ribbons.
  5. AEROPHONE: sound is produced by vibrating air
  6. ELECTRONOPHONES: (not to be confused with ELECTROPHONES) sound is produced by an electronic circuit or digital process and is most often heard through loudspeakers. examples include analog synthesizers, digital samplers/computers
  7. ELECTROPHONES: (This isn’t a specific category but it needs to be added for clarification.) sound is produced either by electronic means or with a vibrating object coupled with a pickup or microphone running through an amplifier and loudspeaker such as electric guitars, electric pianos, PAs, tape machines, and turntables. This category extends into secondary sound producing devices like the microphones, amplifiers, electromagnetic and piezoelectric pickups as well as the entire electronophone category. Most music that we currently listen to is electrophonic on some level.
  8. PHYSIPHONES  (larger classification category): sound is produced from physical phenomina like the elements air, water, fire, earth, etc. Pyrophone produces sound with fire, Hydrophone produces sound with water.

SECONDARY SOUND CLASSIFICATION:

AMPLIFICATION AND RESONANCE

  1. SOUNDBOARDS AND MEMBRANES
  2. SPEAKERS AND PICKUPS
  3. SYMPATHETICS AND REVERB
  4. TUBES AND CONES
  5. SOUND BOX RESONATOR
  6. ELECTROMAGNETS
  7. VENUE AND SPACE

* loudspeakers are fundamentally paper cone membranes that push air in and out actuated by voice coils. Gramaphones have needles fixed to membranes that force air through a horn.

COMPOSITIONAL AND PERFORMATIVE INPUT

  1. HUMAN IMPROVISATIONAL MUSICIANS
  2. GENERATIVE, NATURE,  AND CHANCE
  3. PROGRAMMED AND COMPOSED

 

REFERENCES AND FOOTNOTES


Natural Interfaces for Musical Expression: Physiphones and a physics-based organology by Steve Mann

The Hornbostel-Sachs classification system, based on the Dewey Decimal Classification of library classification, identifies four top-level classifications by their Greek names:

1. idiophone: sound is produced by vibrations in the solid three dimensional body of an instrument. examples include xylophones, gongs, sticks, stones, and other three-dimensional vibrating objects;

2. membranophone: sound is produced by vibrations in a thin membrane. The membrane is principally two dimensional in the sense that the thickness is small compared with the two dimensions of its surface;

3. chordophone: sound is produced by vibrations in a chord (string, wire, dawai, or similar long thin material) principally one-dimensional in the sense that the length is large compared to the two cross sectional dimensions.

4. aerophone: sound is produced by vibrating air;

5. electronophones, later added. These categories are based on identifying the vibrating element that initially makes the sound in the instrument. This taxonomy of (1) solid volume; (2) solid plane; (3) solid line; or (4) gas, limit


Schaeffner’s system (only two top-level categories which he denoted by Roman numerals)

  • I: instruments that make sound from vibrating solids:
    • I.A: no tension (free solid, for example, xylophones, cymbals, or claves);
    • I.B: linguaphones (lamellophones) (solid fixed at only one end, such as a kalimba or thumb piano;
    • I.C: chordophones (solid fixed at both ends, i.e. strings such as piano or harp); plus drums
  • II: instruments that make sound from vibrating air (such as clarinets, trumpets, or bull-roarers.)

The system agrees with Mahillon and Hornbostel-Sachs for chordophones, but groups percussion instruments differently.