Sound waves are everywhere. A very big thanks to the ears, thanks for to the ears for receiving the vibrations that are caused by objects, which travel through material to get to the ears, which will send a message to the brains about the vibrations and how to read them. Sounds are just a form of vibrations. Those vibrations cause many feelings, many emotions, many changes in attitude. Its funny to find out that a beautiful song, is only a mixture of many vibrations making paths through the medium, with different type of pitches and force, that our ears are receiving and transmitting into a beautiful song.
The variations in sound are caused by the different frequencies of vibrations. The difference in the two types of sound waves is; a transverse wave travels just like when you make a rope go up and down, the waves move along in a vertical direction, whereas a longitudinal wave moves in a horizontal direction pushing the waves along. Sound is produced in a saxophone by the player providing a constant flow of air at a pressure above the atmosphere. The constant flow of air from the player is the source of energy, causing the air to oscillate creating vibrations in the air. The vibrating is created by the reed, which controls air flow through the mouthpiece.
is directly computed from the signal. Pitch Synchronous Zero Crossing Peak Amplitudes(PS-ZCPA) is an extension of ZCPA which also considers pitch information. It is found to be more robust to noise than ZCPA. 2) Amplitude-Based Features: Features that are computed from the amplitude of the signal directly are easy and its computation time is fast. MPEG-7 audio waveform is a descriptor that better describes the shape of a waveform on computing the maximum and minimum samples within non-overlapping frames.
Sound is a longitudinal wave. Rapid vibrations of the object create longitudinal or compression waves of sound (Kurtus). Sound has specific characteristics. Sound has wavelengths, frequency, amplitude, and speed or velocity. Wavelength is the distance from one crest of the wave to another.
Generally, people hear sound waves traveling through air. These waves cannot be seen, but are heard or felt via vibration. Sound waves originate from vibrating objects and travel in longitudinal waves through mediums (such as a solid, a liquid, or a gaseous material). These types of waves are defined by the textbook as: “…wave[s] in which the vibrations of the medium are parallel to the direction the wave is moving.1” Figure 8.52 shows an excellent example of a tuning fork producing longitudinal waves, which are perceived as sound. It is apparent that as the prongs are struck, they move outward.
This results in a wave that transmits voice or programming as its amplitude (intensity) increases and decreases. Frequency modulation conveys information, voice, and music on a radio wave is to slightly change, or modulate, the frequency. One big advantage of frequency modulation is that it is static free. AM radio works by changing the amplitude of the carrier wave and FM radio works by changing the frequency of the carrier wave. In amplitude modulation the amplitude of a carrier wave on one specific frequency is modified.
The loudness of a sound perceived by the ear depends on the amplitude of the sound wave and is measured in decibel, while its pitch depends on it frequency measured in hertz, (Shipman-Wilson-Higgins, 2013). We hear sound because circulating conflicts cause the eardrum to vibrate, and feelings are transferred to the acoustic nerve through the fluid and bones of the ear. For example loudness is a relative term. One sound decreases source. As the sound is propagated outward, it is “spread” over a greater area.
Here, three small bones, the ossicles, vibrate in succession to produce a unique pattern of movements that embodies the frequencies contained in every sound we are capable of hearing. The middle ear is also an important component in what music we actually keep out of our 'head'. The muscles grasping the ossicles can contract to prevent as much as two thirds of the sound from entering the inner ear. (1, 2) The mechanical motions of the ossicles directly vibrate a small membrane that connects to the fluid filled inner ear. From this point, vibration of the connective membrane (oval window) transforms mechanical motion into a pressure wave in fluid.
For amplitude modulation the height or amplitude of the wave is changed to contain information. Amplitude modulation is not only used by radio stations but it is also used to send the picture part of television. Pulse modulation is where there are breaks in the wave to indicate the desired information. This is usually used for morse code but can be used for a few other things as well. According to maxwell's equations radio waves travel at the speed of light.
Sounds are produced by the vibrations of material objects, and travel as a result of momentum transfer when air molecules collide. Our ‘subjective impression’ about the frequency of a sound is called pitch. High pitch has high vibration frequency, while low pitch has a low vibration frequency. A pure musical tone consists of a single pitch or frequency. However, most musical tones are “complex summations” of various pure frequencies - one characteristic frequency, called the fundamental, and a series of overtones or harmonics Younger people can usually hear pitches with frequencies from about 20 hertz (infrasonic) to 20,000 (ultrasonic) hertz.