Generally speaking, high-pitched notes are high in frequency and low-pitched notes are low in frequency. When no sound is being sent through the speaker, it rests in its default position. When an audio signal is sent to the speaker, it starts to push outward and pull inward. You can see this in the following image. You can see a much more detailed animation of how a speaker works by Animagraffs.
This is a website that creates amazing 3D models of various technologies. As a speaker vibrates forward and backward, it displaces the air particles in the atmosphere.
This creates a chain reaction through the air from the speaker to our ears. Each time the speaker moves from the default position, to the forward position, to the backward position and returns to the default position, one cycle is completed. Frequency is the number of cycles completed per second.
It is measured in Hertz Hz. The frequency of the musical note A is Hz, meaning the cycle above is completed times per second when this note is played.
This is the A in the middle octave of a piano, called A4. The frequency of the A in the next octave up is Hz. The amplitude of a sound determines the force of the sound wave.
Generally speaking, the higher the amplitude, the louder the sound. In the examples above, the amplitude of the wave is an arbitrary unit of 1. Amplitude is measured in pascals, a unit of pressure. For the purpose of this post, it is only important that you understand the relationship between amplitude and loudness. If you want to get a more in-depth understanding of these concepts, read this post about how sound works and the properties of a sound wave.
The same sheet of music played by a different instrument will sound radically different, even though the same notes are played. This is because each instrument has its own unique tone, or timbre. When the musical note A is played on an instrument, a sound wave is created with a frequency of Hz.
This is the fundamental frequency, or first harmonic. Harmonics are calculated by adding the fundamental frequency to itself again and again. The cycle continues, adding the fundamental frequency each time:. Each instrument that vibrates at Hz will also vibrate at these same harmonic frequencies. The difference between instruments is how loud each harmonic is in comparison to the fundamental frequency.
The following graphs show the frequencies created when the same note is played on various instruments. Notice that the same frequencies are present, but the intensity of these frequencies varies depending on the specific instrument. Fundamental and harmonic frequencies are determined by the dimensions of a sound source. As the string vibrates at its fundamental frequency, it is held in place at each end. There is no motion at the nodes and the greatest motion in the antinodes.
Each instrument has a unique harmonic character. If a clarinet and a piano play notes of the same pitch and loudness, the sounds will still be quite distinct. This is because musical instruments do not vibrate at a single frequency: a given note involves vibrations at many different frequencies, often called harmonics, partials, or overtones. The main factor that causes different sounds in an instrument is the harmonic frequencies and overtones that an instrument outputs on notes, with other factors such as material affecting this factor.
However, when the string is bowed, multiple harmonic frequencies are produced at the same time. The notes will have the same relation to each other on every sheet, but the same notes may be in different places. Many instruments are transposing; the played notes are not the same as the sounded note. So for that instrument the notes are written a step up, so they come out right. There are different clefs, too. Yes … the treble clef note in piano music are the same as flute notes.
The musical range of the flute is far more limited than the piano, and the main elements of flute you will need to master are breath control and finger placement. If you listen very closely to the sound, you will also hear that there are other vibrations happening at the same time. A series of higher pitches will also sound as a result of the fundamental pitch that is played. This series of pitches is called the Overtone Series. Every pitched sound that is made is always identified by the name of the fundamental, but each note is actually a complex series of notes all happening at the same time.
Different instruments naturally will emphasize certain pitches in the overtone series giving them a unique tone that is different from every other instrument. The clarinet, for example, emphasizes just the odd-numbered partials, whereas the oboe is rich in all of them.
The highest partials of the piano are quieter than those of the harpsichord, and they are also more distorted, since the strings of the piano are thicker in relation to their length.
The superior sound of a full-size grand piano is largely due to the longer and relatively thinner strings, which allow more accurate partials and clearer tone. Changes in partials are also an important part of instrument color: Plucked string like those of the guitar begin with many partials and lose the higher ones as the sound dies away; a trumpet not, conversely can begin with relatively few partials and gain more as it progresses.
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