Noise Makers vs Tuned Instruments
Noise making instruments can be fun, mostly for those who are playing with them! Making a tuned instrument is more of a challenge and the opportunities for playing music provide a much more engaging toy. The thumb piano is probably the easiest stable tuned instrument to make and makes a charming sound.
Some Musical Instrument Theory
Sound Making Toys (musical instruments) are split into 4 groups depending on how they make a vibration. The 4 groups are
chordophones , membranophones,
aerophones and ideophones. Can you guess what type of instruments each group is? Each type of instrument has different factors affecting pitch and tone. Making instruments and testing these physical factors is an engaging and rewarding. No two instruments or people sound exactly the same.
A stretched string vibrating
A stretched membrane or skin vibrating
the air vibrating directly
A solid material itself vibrates because of its rigidity, it is not stretched.
Other Useful Jargon
Resonators and Radiators
A radiator is a surface area connected to the primary vibrating object, string, membrane, air or material. Radiators are used to make the sound louder. Strings cannot push much air by themselves. they need to be connected to a larger flexible surface area (radiator, sound board) to make a loud enough sound to be a useful instrument.
A resonator is a container in which sound waves bounce around and are usually reflected out through a sound hole. The resonator gives the instruments sound more sustain (longer lasting). The size, shape and rigidity of the resonating container affect the sound. A guitar has a flexible wood for the soundboard and less flexible wood for the back and sides so they do not absorb the vibration.
The tone of an instrument is created by many frequencies (cycles per second, Hertz) of sound waves all making sound at the same time. If the frequencies have no harmonic relationship (1/2, 1/3, 1/5 etc of the main frequency) the sound will have no pattern and sound like an unpitched noise. A single frequency with no harmonics will sound colourless. A good musical instrument will play a number of related frequencies or Harmonics and have a tone that sounds distinct and pleasant to the ear.
Links to instrument information
Maori Musical instruments
homemade Banjo man
Bart Hopkins book Musical Instrument Design is a treasure trove of information for those who want to take this hobbie to the next level. Here is the page on his website where you can see and hear Bart Hopkins musical inventions