First of all, a sound source radiates power and this results in a sound pressure, where the sound power is the ‘cause’ and sound pressure is the ‘effect’. But still, we always have to keep in mind that sound cannot travel through vacuum, simply, because sound propagates as a wave, which creates ‘compressions’ and ‘rarefactions’, as it interacts with the particles of the medium. If there is no medium, then there are no particles and of course, there is no interaction wave-particles interaction and as a result, no sound is produced. This specific fact, was proven by Robert Boyle (17th century), a researcher who showed through multiple experiments, that a bell, ringing in vacuum medium cannot be heard. We have to mention here, that sound travels in different speed through various media.
Sound can be divided into 2 kinds: Simple and Complex. Imagine a simple tone as a sine wave that comprises of one single frequency, which in fact is the simplest oscillation that can occur in nature. This means, that it cannot be further analyzed in simpler oscillations. The complex sound, on the other hand, consists of a fundamental frequency (which is the lowest one and usually carries most of the intensity) and of some other called overtones. When these overtones are integer multiples of the fundamental (including the fundamental), then we talk about harmonic overtones.
Let’s now examine the qualities of sound. The characteristics of sound can be classified into two categories: Objective and Subjective qualities. Objective qualities are related to the physical properties of sound, such as intensity, frequency and frequency spectrum, which can be measured by the use of specific instrumentation. On the other hand, the term ‘subjective’ refers to the ...
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...r sound pressure level) are the same. The so-called Fletcher & Munson curves show that.
These curves are based on the work of Fletcher and Munson at Bell labs in the 30’s, or better, we could say that they are refinements made more recently by Robinson and Dadson. These were made by asking people to judge when pure tones of two different frequencies were the same loudness. Because of the fact that this is a very difficult judgement to make, and the curves are the average results from many subjects, they should be considered as general indicators rather than a prescription as to what a single individual might hear. As you can see in the following chart, the 60 phons curve crosses the dB scale at 60 for 1KHz. For us to perceive e.g. 40Hz as the same volume as 1KHz, it will need approximately 20dB more power (the 60 phons curve meets 40 Hz at about 82 on the Y-axis).
The purpose of this experiment was to determine whether if the sound is affected when it travels through different length pipes. The method used to do this experiment was created by using 5 different PVC pipes in the lengths of 10, 20, 30, 40, and 50 centimeters. Then, using a tuning fork, sound will be produced on one end of the PVC pipe and measured with a decimeter on the other end. This experiment was recorded using 5 trials for each independent level and the average decibels (dB) for each pipe length were recorded.
Most people are familiar with the word "music", however they barely consider the definition of it. After carefully think, everyone has their own opinions on this term and it is hard to have an uniform criterion of music sounds. According to the text book, Michael B. Bakan states five propositions to define the music. The first one is about the tone and the second one talks about the music is organized in some way. The next two are claims that music is human organized and a product of human intention and perception. The last proposition argues music cannot separate from Western culture. Among these propositions, I think the music is a product of human intention and perception is most interesting and worth to discuss. So I assert that the most
At any point in the air near the source of sound, the molecules are moving backwards and forwards, and the air pressure varies up and down by very small amounts. The number of vibrations per second is called the frequency which is measured in cycles per second or Hertz (Hz). The pitch of a note is almost entirely determined by the frequency: high frequency for high pitch and low for low .
In general, audio coders operate by decomposing the signal into a set of units, each corresponding to a certain range in time and frequency. Using this time-frequency distribution, the signal is analyzed according to psychoacoustic principles.
To supplement visual observations, the analyst can often use non-visual information. Describe two examples of auditory information that could be used during a qualitative analysis.
A transducer is a mechanism that changes one form of energy to another form. A toaster is a transducer that turns electricity into heat; a loudspeaker is a transducer that changes electricity into sound. Likewise, an ultrasound transducer changes electricity voltage into ultrasound waves, and vice versa. This is possible because of the principle of piezoelectricity, which states that some materials (ceramics, quartz, and others) produce a voltage when deformed by an applied pressure. Conversely, piezoelectricity also results in production of a pressure whe...
Music is far more than the sum of its parts. It can be thought of in a highly mathematical sense, which leaves one in awe of the seemingly endless combinations of rhythm, tone and intervals that a good musician can produce. Admiring music in this way is a lot like admiring an intricate snowflake, or shapes in the clouds; it's beautiful, but at the same time very scientific, based on patterns. All of the aforementioned qualities of music have one thing in common: they can be defined with numeric, specific values. However, the greatest aspect of music lies elsewhere, and cannot be specifically defined with words. It is the reaction that each individual has when they are confronted with their favorite (or least favorite) kind of music.
The terms homophony and polyphony are both musical voices. The former can be defined as one sound or line of melody at a time that is played by multiple instruments at the same time, while the latter is any music with two or more independent melodic parts sounded together. Homophony music is one melodic line at a time, the other voices or parts serving as accompaniment. Polyphony music, on the other hand, is combined with several lines of a similar, rhythmically identical design. The terms homophony and polyphonic are types of a musical texture as well. The most common definition of texture, in a general sense, is the visual or tactile surface characteristics and appearance of something. The following qualifiers "rough", "smooth", "coarse", "silken", "thin" and "thick" are mostly accompany the term to describe certain characteristics of textiles. Its definition as a musical term is the overall quality of a sound of a piece, most often indicated by the number of voices in the music as well as the interaction of melodies and harmonies within a song. Homophonic texture can be found in the most popular music styles, such as folk, rock, country, jazz, etc. and also can be accompanied with a vocal music. Polyphonic, in contrast, described as thicker or
Sounds are produced by the vibrations of material objects, and travel as a result of
The vibration of the strings of a guitar causes the sound wave, but is not actually what you are hearing. The amplification of the sound wave is what is actually heard. The differences in the tension of the stings and the mass of the strings affect the pitch of the sound produced. The ends of each string are nodes, or where the wave does not travel from its initial position. The note you hear from the string is actually the first harmonic of the wave; other harmonics created when plucking a string form the undertones and overtones of a note. The waves on a guitar string are transverse waves, meaning they travel perpendicular to the original position. The waves are also standing waves, because they remain in the same position.
The voice is our primary mean of communication and expression. We rarely last more than a few minutes without its use whether it is talking to someone else or humming quietly to ourselves. We can use the voice artistically in many ways. For example, singing carries the rhythm and melody of speech. It creates patterns of pitch, loudness, and duration that tie together syllables, phrases and sentences. We use the voice for survival, emotion, expression, and to reflect our personality. The loss of the voice is a severe curtailment to many professions. It is affected by general body condition which is why we need to consider the location of the larynx and how that organ produces voice. Surprisingly, this complex biological design is mechanical in function. It is mechanical to the point that when it has been excised from a cadaver and mounted on a laboratory bench, the larynx produces sounds resembling normal phonation. (Titze, Principles)
The sound waves for open ended and string instruments is fairly straight forward. However, for a closed end instrument, such as a drum, the sound waves are different. A lot of the energy is dissipated through the shell of the drum, which is the reason for the variance in drum construction these days. Many different kinds of wood are used to generate different sounds, or a different amount of energy absorption. For a warmer, deeper sound maple construction is used while birch is used to get a high, resonant tone full of vibration. The heaviest wood that dissipates the most amount of energy is oak, creating a lower, flat sound.
Sound is produced by vibrations in the air which, in this experiment, came from the hammer. The vibrations are a set of frequencies measured in units of Hertz (Hz). The faster the vibration frequency, the higher the sound will be in pitch. Pythagoras’s 2:1 ratio simply means that both tones are the same however the second tone’s frequency rate is doubled. For example, the blacksmith strike...
What is the importance of sound in TV or Film, and how can it be used creatively in driving the narrative forward?
Speaking of how the human ear receives music, sound is produced by vibrations that transmits energy into sound waves, a form of energy in which human ears can respond to and hear. Specifically, there are two different types of sound waves. The more common of the two are the transversal waves, which ...