Introduction:
In 1986, designers at Sony began the quest to develop a sound medium that combined the benefits of the compact disc, such as sound quality and track accessibility, with the recordability of the cassette tape, in a player with unprecedented portability. They gave engineers the task of creating what would later be called the Minidisc, a wallet sized unit that could record, play, and store music on cartridge enclosed discs. Engineers integrated several technologies to produce the Minidisc, all utilizing the laws of physics. They found that:
-Laser optics would be the obvious choice for reading data.
-Magneto optic technology would be created to record information.
-To allow recordability, new disc properties had to be defined.
-Compression and acoustic principles would be incorporated to store information on a disc 1/5 the size of the compact disc.
The laser used in the minidisc player serves two purposes. Its primary role is to read digital information in a similar fashion as a CD player. Its secondary, but equally important, function is to supply focused heat to the minidisc itself during the recording process.
LASER HEAT: The minidisc recording system takes advantage of a discovery by Pierre Curie in the 1880's. He found that when iron is heated up to a certain temperature, now called the Curie point, it loses its magnetic properties. Similarly, when the minidisc laser is directed at a tiny point of the disc during recording, it heats that spot up to 180 degrees celsius, and the disc material loses its magnetic properties. A magnetic field can then be "frozen" onto that point once it moves past the laser beam, storing data. For more information on the recording process, visit...
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...o-acoustic principles, which states that the ear is more sensitive to some frequencies of sound than others. Psychoacoustics also explores the relationship between the intensity of sound (its decibel level) and its frequency. As you can see from the equi-loudness curve below, a low frequency, high intensity wave will produce the same loudness as a high frequency, low intensity wave.The masking of sound is another factor considered during the compression process. This occurs when one sound blocks another sound from being heard. For example, on a crisp fall day you would be able to hear leaves rustling in the wind until a marching band stomps by. ATRAC would omit the rustling leaves data that was masked by the band, saving storage space. Once the audible sound data is singled out, it can easily be compressed and stored with an inperceivable change in sound quality.
Web. 15 Feb. 2014. <http://www.sciencetech.technomuses.ca/english/collection/disk_play.cfm>. Edie, Paul C. "History of the Victor Phonograph." The Victor-Victrola Page.
12. DVDs are digital versatile disc, optical discs used to externally store data. DVDs have higher recording and retrieving speeds, are better suited for backing up information, and have higher capacity per device than
Briton Kane Kramer invented the digital audio player in 1979, known as the MP3 player. Finally, the compact discs (CD) came out in 1982 and “The first album ever released on a CD was Billy Joel’s 52nd Street. The first to sell one million copies was Dire Straits’ Brothers In Arms.” Following the CD were: DAB radio, Sony Discman, Sony Minidisc.... ...
Preview of Main Points: I will explain the history of the vinyl record and how they are made.
In the late 1890s, the concept of self-playing piano start to capture the attention of the inventors and the public and several different inventors’ mechanisms were marketed. Player piano has all the characteristic of a piano and it can play by itself. Piano designer and inventor Melville Clark had his very first instrument “Apollo Player Piano”, built with 88note standard in 1901 caused a major impact on the music industry. Player piano is the very first widely successful consumer device that was able to encode the data in binary format. This was done by hand punching rolls ...
How a record player works is quite simple. A motor is somehow connected to a solid disc so that the disc is rotated at a constant speed. On top of the rotating disc (platter), The record is placed on top, with a slip mat in between. The slip mat can serve two functions. In the past to hold the record in place so that it would not rotate independently of the platter. Now, however, the slip mat serves a much different function. Instead of holding the record in place, the slip mat is now used to reduce the friction between the spinning platter and the record. This way a DJ can scratch (manually move the record, usually at high speeds) the record while the platter continues to spin underneath. Once the record is rotating, a stylus glides along the grooves and picks up the vibrations, these are then converted into audible sound.
There are a few different physics engines that programmers use now for their games. There are 2 main physics engines that programmers use: Havok, and Math Engine.
Edison decided to change the idea by using a tin foil wrapped metal cylinder instead of the paper. The final cylinder phonograph had 2 diaphragm and needle units. One would be for recording date and the other would be for playing it. For the machine to work, one would have to speak into a mouthpiece and the sound vibrations would be imprinted on the cylinder. Then the recording needle would create some sort of groove pattern on the cylinder. The data can then played by back by the data from the created grooves.
Most of the applications in terms of speech and audio compression may seem obvious at first, but what most do not realize is the scale at which it is used. Some of the more common examples include: telephone communications, compact disc players in the form of digital audio coding, stereo sound systems, speech recognition and playback, noise reduction/filtering after voice recognition and speech synthesis [1]. The uses of DSP for speech and audio compression is certainly not limited to these examples, but just these alone are examples that the general public use through various devices on a daily basis often without realizing the function of the systems and processes that go into their operation.
...ats such as paper based and microfilm. Compare to paper based, it does not change the form of paper even how many years pass. With the proper care of the records, record center or an organization can keep the record almost thirty years until the process of destruction. However, it could not happen to an electronic record, because technologies rapidly change. There always have new software or hardware that will be upgrade and become more advance. Actually, even under the best storage conditions, digital media have a very limited shelf life, generally less than thirty years. The efforts to preserve the physical media thus provide only a short term, partial solution to the general problem of preserving digital information. Given such rates of technological change, even the most fragile media may well survive the continued availability of equipment to read those media.
Each of the senses receives a different stimulus that allows us to perceive that specific type of information. For hearing the stimulus is sound waves. These are waves of pressure that are conducted through a medium (Martini, 2009). Often this medium is air but it can also be water or a solid object. Each wave consists of a region where the air molecules are gathered together and an opposite region where they are farther apart (Martini, 2009). A wavelength is the distance between either two wave peaks or two wave troughs. The number of waves that pass through a fixed reference point in a given time is the frequency. High pitch sounds have a high frequency where as low pitch sounds have a low frequency (Myers, 2010). The amplitude is the amount of energy, or intensity, in a sound wave. The more energy that a sound wave has, the louder it seems. For us to perceive any of the sound waves around us, they must pass through the external, middle, and inner ea...
Sure, there are times when we listen carefully to the music behind the songs we hear, we may focus on the rhythm or the harmonies, but we never think of what it took to make the sounds that we are hearing. In this paper, I will explain the physical musical instruments. I will describe and define sound in psychic terms and then describe how different instruments create their unique sounds. There are so many different kinds of music, and thanks to the variety of instruments, the combinations of sounds that we can make are limitless. Before we look at musical instruments, we have to look at music itself.
What distinguishes sound waves from most other waves is that humans easily can perceive the frequency and amplitude of the wave. The frequency governs the pitch of the note produced, while the amplitude relates to the sound le...
Before understanding the physics principles, one must understand the physical design that induces them. A magnetic disk is a flat, circular, rigid sheet of aluminum coated with a layer of magnetic material (can be double sided). The material usually is a form of iron oxide with various other elements added. The disk rotates upon a central axis and a movable read/write head writes information along concentric tracks (circular paths traced out by motion of the disk) on it. Multiple disks can be stacked to store more information. Typically (1985) 11 disks with 22 surfaces, of which 20 are used (minus top/bottom), are manipulated to read/write data.
There are several different storage devices that can be used to store your data. These are the magnetic storage, optical storage, and solid state storage. According to Parsons and Oja (2014), “a magnetic storage devices stores the data by magnetizing microscopic particles on a disk or tape surface” (p