1. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Musical Instruments Howard & Angus, Chapter 4 www.phys.unsw.edu.au

2. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Any acoustic instrument has two main components:  a sound source, and  sound modifiers. e.g., echo, reflection, absorptionStudent project

3. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Student project Hearing music in different environments

4. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Stringed instruments The string family of musical instruments includes the  violin, viola, violoncello, double bass and all their predecessors  keyboard instruments use of strings, such as the piano, harpsichord, clavichord and spinet

5. A.Diederich – International University Bremen – USC – MMM – Spring 2005  All stringed instruments consist of one or more strings stretched between two points.  The fundamental frequency produced by the string is dependent on its mass per unit length, length and tension.  The mass per unit length of an individual string is constant and changes are made to the tension and/or length to enable different notes to be played. bridge variable mass

6. A.Diederich – International University Bremen – USC – MMM – Spring 2005  The string is set into vibration to provide the sound source to the instrument.  A vibrating string on its own is extremely quiet because …?  All practical stringed instruments have a body which is set motion by the vibrations of the string(s) of the instrument.  The body of the instrument is the sound modifier.

7. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Three main methods by which energy is provided to a stringed instrument:  plucked (e.g., violin family, guitar lute)  bowed (e.g., violin family)  struck (e.g., piano) (A vibrating string fixed at both ends has a unique set of standing waves.)

8. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Sound modifiers in stringed instruments  The sound source provided by a plucked of bowed string is coupled to the sound modifiers of the instrument via a bridge.  The vibrational properties of all elements of the body of the instrument play a part in determining the sound modification that takes place.

9. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Example: Violin family  top plate ( the plate under the string which the bridge stands on and which has the f holes)  back plate  the air contained within the main body of the instrument  Less:  glues, varnish, choice of wood, wood treatment

10. A.Diederich – International University Bremen – USC – MMM – Spring 2005

11. Wind instruments

12. A.Diederich – International University Bremen – USC – MMM – Spring 2005 The main parts of flue (open metal and stopped wood) and reed organ pipes

13. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Sound source in organ flue pipes The important features of a flue sound source are a narrow slit (the flue) through which air flows, and a wedge- shaped obstacle placed in the airstream from the slit.

14. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Sound modifiers in organ pipes  The sound modifier in a flue organ pipe is the main body of the pipe itself, or its "resonator".  The most straightforward are resonators whose dimensions do not vary along their length.  Two basic types: open or stopped at the end  The fundamental frequency of air reed vibration is entirely controlled by:  the length of the resonator  whether the pipe is open or stopped

15. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Recorder and flute  The length of the resonator is changed by means of finger holes.  To play a second octave the flue is overblown.

16. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Brass instruments The sound source in brass instruments is the vibrating lips of the player in the mouthpiece

17. A.Diederich – International University Bremen – USC – MMM – Spring 2005  The basic valve combinations used on brass instruments to enable seven semitones to be fingered.  Black circle = valve depresses  White circle = valve not depressed  On a trumpet, first valve is nearest the mouthpiece, second in the middle, and third nearest the bell

18. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Percussion instruments

19. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Sound source and sound modifiers  The sound source in percussion instruments usually involves some kind of striking. (Impulse, all frequency components, non- periodic)  Three classes of percussion instruments, using  bars (e.g., xylophone, glockenspiel, céleste, triangle)  membranes (e.g., drums)  plates (e.g., cymbals)

20. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Two categories regarding pitch  Those with a definite pitch, on which a melody can be played.  Those with an indefinite pitch, on which a melody cannot be played.

21. A.Diederich – International University Bremen – USC – MMM – Spring 2005 Definite PitchIndefinite Pitch Timpani Bass Drum Celesta Side Drum XylophoneCymbal Glockenspiel Gong Tubular Bells Triangle Tambourine Castanets Wooden Block

22. A.Diederich – International University Bremen – USC – MMM – Spring 2005

23. Student Project A truly psychological question: Musicians and instruments: Are there any personality characteristics? or Are trombone players different from violinists?