Audio electronics:

Introduction:

Devices that reproduce, record, or process sound are referred to as audio equipment. This covers headphones, speakers, amplifiers, mixing consoles, CD players, tape recorders, radio receivers, and AV receivers.

 

Audio electronics

In many various settings, including concerts, clubs, conference rooms, and the home, audio equipment is frequently utilized to reproduce, record, and amplify sound.

 

In addition to performing certain signal processing tasks, electronic circuits regarded as being a part of audio electronics may also be built to make specific changes to the signal while it is in the electrical form.

 

Electric signals produced by electrical devices can be used to artificially produce audio signals.

 

Up until the development of advanced digital technology, analog electric circuit techniques were typically used to construct audio devices. Furthermore, due to its compatible digital nature, digital signals can be altered by computer software in a manner similar to how audio electronic equipment would. Both analog and digital design formats are still in use today, and whether one is best for a given application mostly depends on it.

 

The electrical, mechanical, electronic, or digital inscription and creation of sound waves, such as spoken speech, singing, instrumental music, or sound effects, is known as sound recording and reproduction. Analog recording and digital recording are the two basic categories of sound recording technology.

 

Sound recording is the process of transferring inaudible air vibrations to a storage media, like a phonograph disc. In sound reproduction, the process is reversed, and the variations stored on the medium are converted back into sound waves.

 

A microphone diaphragm monitors variations in atmospheric pressure brought on by acoustic sound waves and records them as a mechanical representation of the sound waves on a media like a phonograph record to create an acoustic analog recording (in which a stylus cuts grooves on a record). In magnetic tape recording, sound waves cause the microphone diaphragm to vibrate. This electric current is then changed into a changing magnetic field by an electromagnet, which creates magnetized patches on a plastic tape that has a magnetic coating. The opposite is true for analog sound reproduction, where a larger loudspeaker diaphragm modifies ambient pressure to produce acoustic sound waves.

 

By means of sampling, digital recording and reproduction transform the analog sound signal captured by the microphone into a digital format. As a result, a larger range of media can store and transmit audio data. When audio is recorded digitally, it is stored as a series of binary values (zeroes and ones) that represent samples of the audio signal's amplitude taken at regular intervals and at a sample rate that is high enough to transmit all sounds that are audible. Prior to being amplified and linked to a loudspeaker in order to produce sound, a digital audio stream must be converted back to analog during playback.

 

Instrumental music may be encoded and reproduced mechanically before the invention of sound recording, such as with wind-up music boxes and later player pianos.

 

Audio electronics

History:

Music was first recorded long before sound appeared, initially using written music notation and then mechanical instruments (e.g., wind-up music boxes, in which a mechanism turns a spindle, which plucks metal tines, thus reproducing a melody). The Ban Ms brothers created the earliest known mechanical musical instrument in the 9th century, a hydropowered (water-powered) organ that played interchangeable cylinders, which is when automatic music reproduction was first introduced. Charles B. Fowler claims that until the second half of the nineteenth century, this "cylinder with elevated pins on the surface remained the primary mechanism to make and reproduce music mechanically." The Ban Ms brothers also created what appears to have been the first programmable machine, an automatic flute player.

 

Although this notion has not been definitively proven, carvings at the Rosslyn Chapel from the 1560s may be an early attempt to record the Chladni patterns generated by sound in stone representations.

 

In Flanders, a mechanical bell-ringer operated by a rotating cylinder was first used in the fourteenth century. Similar styles also arose in music boxes, musical clocks (1598), barrel pianos (1805), and barrel organs in the 15th century (ca. 1800). An automatic musical instrument known as a music box makes sounds by using a set of pins that are positioned on a rotating cylinder or disc to pull the lamellae or tuned teeth of a steel comb.

 

The 1892 carnival organ employed an accordion-folded system of perforated cardboard booklets. A long piece of music could be stored on the player piano's punched paper scroll, which was first exhibited in 1876. The most complex piano rolls were "hand-played," which refers to copies made from a master roll made on a unique piano that made holes in the master as a live musician played the tune. In this way, the roll reflected more than just the more usual practice of punching the master roll through transcription of the sheet music; it was a recording of a person's real performance. It took until 1904 for the ability to capture a live performance onto a piano roll to be created. From 1896 through 2008, piano rolls were produced in large quantities continuously. In a 1908 copyright decision, the U.S. Supreme Court stated that between 1,000,000 and 1,500,000 piano rolls and 70,000 to 75,000 player pianos were made in just 1902.

 

Analogue electronics:

Introduction:

Contrary to digital electronics, where signals typically take only two levels, analog electronics are electronic systems with a continuously changeable signal. The proportional relationship between a signal and a voltage or current that represents the signal is referred to as "analog." The Greek word "analogueos," which means "proportional," is the source of the English word analogue.

 

Analogue electronics

An analogue signal transmits information using a property of the medium. An angular location of a needle, for instance, is used as a signal by an aneroid barometer to indicate changes in air pressure. Changes in electrical signals' voltage, current, frequency, or overall charge can be used to convey information. A transducer, which transforms one form of energy into another, translates information from another physical form (such as sound, light, temperature, pressure, or position) to an electrical signal (e.g. a microphone)

 

Each distinct signal value reflects a different piece of information, and the signals can take any value from a predetermined range. Each level of the signal indicates a distinct level of the phenomenon it describes, and any change in the signal is significant. Consider the signal as a temperature indicator, with one volt standing in for one degree Celsius. According to this approach, 10 volts correspond to 10 degrees, and 10.1 volts to 10.1 degrees.

 

Analogue electronics

The use of modulation is an additional means of transmitting an analog signal. This includes changing one or more aspects of a basic carrier signal. Amplitude modulation (AM) modifies the amplitude of a sinusoidal voltage waveform while frequency modulation (FM) modifies the frequency. There are many other methods, such phase modulation or altering the carrier signal's phase.

 

The variation in the sound pressure that strikes a microphone during an analog sound recording causes a corresponding variation in the current or voltage across the microphone. The current or voltage fluctuation grows proportionally as the sound level fluctuates while maintaining the same waveform or shape.

 

Analog signals can be used in mechanical, pneumatic, hydraulic, and other systems.

 

Random disturbances or fluctuations, some of which are brought on by the random thermal vibrations of atomic particles, are invariably present in analog systems. Any disturbance is comparable to a change in the original signal and appears as noise since all variations of an analog signal are significant. These random changes become more severe and cause signal deterioration as the signal is copied and recopied or sent across extended distances. Crosstalk from other signals or components that are poorly built could be additional sources of noise. Utilizing low-noise amplifiers and shielding both help to lessen these problems (LNA).

 

Analog and digital electronics interpret signals in different ways because the information is encoded in them differently. In the digital realm, all operations that can be applied to an analogue signal, such as amplification, filtering, limiting, and others, can also be carried out. Because any digital circuit's behavior can be explained using the principles of analogue circuits, every digital circuit is also an analog circuit.

 

Utilizing microelectronics has reduced the cost and increased accessibility of digital gadgets.

 

The level of the noise determines how it affects an analog circuit. The analogue transmission gets affected increasingly and loses use over time as noise level rises. Analog signals are considered to "fail gracefully" as a result. Intelligible information can still be found in analogue signals even when there is a lot of noise present. Contrarily, digital circuits are completely unaffected by noise up to a specific threshold, after which they experience catastrophic failure. The use of error detection and repair coding methods and algorithms for digital telecommunications can raise the noise threshold. However, there is still a point at which the link catastrophically fails.

 

Because the information in digital electronics is quantized, a signal can represent the same information as long as it stays within a given range of values. At each logic gate in digital circuits, the signal is regenerated, reducing or eliminating noise. [failed to verify] Signal loss in analog circuits can be recovered using amplifiers. But noise builds up over the entire system, and the amplifier itself will amplify the noise in accordance with its noise figure.

 

The amount of noise in the original signal and the noise that processing adds are the key elements that impact how precise a signal is (see signal-to-noise ratio). The resolution of analogue signals is constrained by fundamental physical factors like shot noise in components. In digital electronics, extra precision is provided by representing the signal with more digits. Since digital operations can typically be done without losing precision, the analogue-to-digital converter's (ADC) capability determines the practical limit for the number of digits. An analog signal is converted into a string of binary integers by the ADC. The ADC can be used in straightforward digital display devices like thermometers and light meters, but it can also be utilized for data collecting and digital sound recording. A digital signal is converted to an analog signal using a device called a digital-to-analog converter (DAC). A DAC transforms a stream of binary numbers into an analog signal. A DAC is frequently found in an op-gain-control amp's system, which may then be used to operate digital amplifiers and filters.

 

Analogue electronics

When compared to analogous digital systems, analog circuits are often more difficult to conceptualize. This is one of the primary causes of the rise in popularity of digital systems over analog ones. As opposed to digital systems, analogue circuits are typically constructed by hand and with far less automation. Since the early 2000s, platforms have been created that make it possible to describe analog design using software, allowing for quicker prototyping. A digital electronic gadget will, however, always require an analog interface in order to communicate with the outside world. For instance, the initial stage of the receive chain in every digital radio receiver is an analog preamplifier.

 

The only components in an analog circuit are resistors, capacitors, and inductors. Transistors and other active components are found in active circuits. Discrete components, or lumped parts, are used to construct conventional circuits. Distributed-element circuits, constructed from segments of transmission line, offer an option.