musical instruments and resonance Flashcards
What is the Hornbostel-Sachs system?
A classification system for musical instruments based on their method of sound production
It divides instruments into five main categories: idiophones, membranophones, chordophones, aerophones, and electrophones.
Define idiophones.
Instruments that produce sound by the vibration of sonorous material
Examples include xylophones, cymbals, and kalimbas.
What are membranophones?
Instruments that create sound by the vibration of a stretched membrane
Examples include drums and kazoos.
What defines chordophones?
Instruments that produce sound through the vibration of a stretched string
Types include plucking (guitar), bowing (violin), striking (piano), and rubbing (hurdy-gurdy).
What are aerophones?
Instruments that produce sound by the vibration of a column of air
Examples include flutes, trumpets, and organs.
What are electrophones?
Instruments that produce sound through a vibrating loudspeaker driven by an amplifier
They include electric instruments, acoustic instruments with electric amplification, and instruments generating sound electrically, like synthesizers.
What is resonance?
The phenomenon that occurs when a driving frequency matches the natural frequency of an oscillating system
An example is pushing someone on a swing.
Define oscillation.
A periodic motion about a point of equilibrium
An example is the motion of a pendulum.
What is free oscillation?
When a system is excited and then allowed to vibrate freely without external forces
Examples include plucking a string or striking a drum.
Define forced oscillation.
When an external force is continually applied to a system
Examples include bowing a string or blowing into a wind instrument.
What are nodes and anti-nodes in standing waves?
Nodes are points of zero displacement, while anti-nodes are points of maximum displacement
These occur in standing waves formed in oscillating strings.
What is a standing wave?
A wave that forms in a medium when the driving frequency corresponds to a natural frequency
It is characterized by nodes and anti-nodes.
What is Helmholtz resonance?
The resonance of a cavity of air
It explains the behavior of air-filled spaces in producing sound.
Fill in the blank: A _______ is created when an oscillating force acts on a stretched string at its natural frequency.
standing wave
True or False: The frequencies of standing waves on a vibrating surface usually form a harmonic series.
False
