In the mid-1870s, a form of amplitude modulation — initially called " undulatory currents "— was the first method to successfully produce quality audio over telephone lines.

Stand-alone, file based, multi-track recorders from Sound Devices, This of course results in a reduction in audio quality, but a variety of techniques are used, mainly by exploiting psychoacoustics, to remove the data that has least effect on perceived quality.

To compensate for this, GCC ’ s engineers allowed games to include a POKEY audio chip in the cartridge which substantially improved the audio quality.

The gain of a good quality full-range audio amplifier will be essentially flat between 20 Hz to about 20 kHz ( the range of normal human hearing ).

A seven-person project group was formed to develop an optical audio disc with a diameter of 20 cm with a sound quality superior to that of the large and vulnerable vinyl record.

The demonstration showed that it is possible by using digital optical recording and playback to reproduce audio signals with superb stereo quality.

The new audio disc was enthusiastically received, especially in the early-adopting classical music and audiophile communities, and its handling quality received particular praise.

The acceptable trade-off between loss of audio quality and transmission or storage size depends upon the application.

Due to the nature of lossy algorithms, audio quality suffers when a file is decompressed and recompressed ( digital generation loss ).

In contrast, lossy compression ( for example JPEG, or MP3 ) can achieve much higher compression ratios at the cost of a decrease in quality, as visual or audio compression artifacts from loss of important information are introduced.

This process whereby an actor rerecords lines spoken during filming in order to improve audio quality or reflect dialogue changes is called Automated Dialogue Replacement ( ADR ), also known as Additional Dialogue Recording.

The power gain of an amplifier depends on the source and load impedances used as well as its voltage gain ; while an RF amplifier may have its impedances optimized for power transfer, audio and instrumentation amplifiers are normally employed with amplifier input and output impedances optimized for least loading and highest quality.

High quality class-D audio amplifiers have now appeared on the market-these designs have been said to rival traditional AB amplifiers in terms of quality.

The term can also be used as an explanation for the poor quality of a digitized audio or video file.

The game's own CD contained soundtrack in audio format that was exactly the same as the game's MIDI soundtrack but played through a high quality sound module.

High fidelity — or hi-fi or hifi — reproduction is a term used by home stereo listeners and home audio enthusiasts ( audiophiles ) to refer to high-quality reproduction of sound to distinguish it from the poorer quality sound produced by inexpensive audio equipment, or the inferior quality of sound reproduction characteristic of recordings made until the late 1940s.

DIN 45500 approval was intended to provide audio equipment buyers with reassurance that their equipment was capable of good quality reproduction.

Scientific double-blind tests are often used to disprove certain audio components ( such as expensive, exotic cables ) have any perceivable effect on sound quality.

ISDN is used heavily by the broadcast industry as a reliable way of switching low latency, high quality, long distance audio circuits.

Beginning with Reginald Fessenden's audio demonstrations in 1906, it was also the original method used for audio radio transmissions, and remains in use today by many forms of communication —" AM " is often used to refer to the mediumwave broadcast band ( see AM radio ).

Most of the Project's titles, especially the early work, share common traits ( likely influenced by Pink Floyd's The Dark Side of the Moon, on which Parsons was the audio engineer in 1973 ).

The first model was launched in 1985 as a high-end home computer and became popular for its graphical, audio and multi-tasking abilities.

The PowerPC CPU on PowerUP boards is usually used as a coprocessor for heavy computations ( a powerful CPU is needed to run MAME for example, but even decoding JPEG pictures and MP3 audio was considered heavy computation at the time ).

The Electron was able to save and load programs onto audio cassette via a supplied converter cable that connected it to any standard tape recorder that had the correct sockets.

This encoding was native to the SPARCstation 1 hardware, where SunOS exposed the encoding to application programs through the / dev / audio interface.

It was also the first BBS to produce audio for its visitors, broadcasting news about screen printing and music in a pre-recorded method in what was the precursor to Internet Radio.

* During the famous viral marketing for The Dark Knight, an audio clip was available that depicted Harvey Dent walking up to a hostage situation and subduing the threat.

It was originally developed to store and play back sound recordings only, but the format was later adapted for storage of data ( CD-ROM ), write-once audio and data storage ( CD-R ), rewritable media ( CD-RW ), Video Compact Discs ( VCD ), Super Video Compact Discs ( SVCD ), PhotoCD, PictureCD, CD-i, and Enhanced CD.

In 1974, an initiative was taken by L. Ottens, a director of the audio industry group within the Philips Corporation in Eindhoven, the Netherlands.

Counter-Strike received a major technology update and refresh on November 1, 2004 with the release of Counter-Strike: Source, which was heavily updated using Valve's Source game engine to take advantage of more modern graphics and audio hardware.

The innovation of lossy audio compression was to use psychoacoustics to recognize that not all data in an audio stream can be perceived by the human auditory system.

A literature compendium for a large variety of audio coding systems was published in the IEEE Journal on Selected Areas in Communications ( JSAC ), February 1988.

The world's first commercial broadcast automation audio compression system was developed by Oscar Bonello, an Engineering professor at the University of Buenos Aires.

Throughout the 1980s and ' 90s, Young promised fans a follow-up to the original Decade collection, provisionally titled Decade II ; eventually, this idea was scrapped in favor of a much more comprehensive anthology to be titled Archives, spanning his entire career and ranging in size from a box set to an entire series of audio and / or video releases.

A slightly earlier, surprisingly reliable version of the same concept was to bundle a sequence of audio digital " signal " and " no signal " information ( i. e. " sound " and " silence ") on magnetic cassette tape for use with early home computers.

Because the audio was relayed over the internet, it was possible to access internet radio stations from anywhere in the world.

For some years following the introduction of solid state amplifiers, their perceived sound did not have the excellent audio quality of the best valve amplifiers ( see valve audio amplifier ).

Advocates of digital point to the high levels of performance possible with digital audio, including excellent linearity in the audible band and low levels of noise and distortion.

was too expensive, and it gave them excellent DOS support, a feature that was proving difficult for companies to get working with PCI cards ( as described above in the Sound Blaster 16 section, early PCI audio cards had to work around the missing ISA-DMA lines of the PCI slot to run with existing DOS software, and often the work-arounds did not function well, or worked only in DOS boxes within Microsoft Windows ).

Although magnetic audio was of excellent quality it also had significant disadvantages.

Originally the term " Hi-Fi " meant high fidelity sound, excellent and organic audio.

" They specifically praised its graphics and audio, calling the latter " excellent ".

It didn't help that the audio section of the card was not particularly excellent either, receiving luke warm reviews regarding MIDI quality ( extremely important during the card's time ).

* The Arabic text of ten Muallawqat, with excellent audio tracks of their recitations