Linear Acoustic

Last updated
Linear Acoustic
Company type Private
Industry Broadcasting
Founded2002
FounderTim Carroll
Headquarters,
ProductsLoudness controllers, loudness monitors and meters, DTV audio encoders and transcoders
Website www.linearacoustic.com

Linear Acoustic is an American company based in Lancaster, Pennsylvania that develops technology and manufacturers equipment used by television stations, cable television and satellite television services providers, post-production facilities and other content services providers to control, measure, manage and monitor multi-channel digital audio. The company has been especially active in areas related to automated upmixing [1] and downmixing of multichannel broadcast audio, and with issues related to relative loudness of broadcast audio.

Contents

The company was founded in 2002 by Tim Carroll, who had previously worked as Product Manager for the Professional Audio Division [2] of Dolby Laboratories in San Francisco. While at Dolby, Carroll contributed to the development of Dolby Digital (AC-3) and Dolby E encoding systems for DVD and high-definition television (HDTV) applications. Christina Carroll is the Vice President and Executive Director of Linear Acoustic and is responsible for managing day-to-day company operations.

The companys products can be broadly broken down into three categories: Loudness controllers designed to help television broadcasters maintain consistent audio levels; monitors and meters that measure digital audio levels, including loudness; and stand-alone encoding and transcoding products for handling the various data compression technologies commonly found in digital television plants.

The subject of controlling loudness in television broadcasts has garnered considerable publicity [3] since the FCC moved to implement enforcement of the Commercial Advertisement Loudness Mitigation or CALM Act on December 13, 2012. While consumer complaints about overly loud television commercials are almost as old as the medium itself, [4] the CALM Act began as legislation was first sponsored by Representative Anna Eshoo, a Democratic congresswoman in California, in 2008. The law was passed in 2010 and went into full effect in 2011 and 2012. [5]

The Linear Acoustic AERO line of audio processors effectively measures and manages shifts in loudness and controls discrepancies between program and commercial audio without unnecessarily degrading the quality of the audio or significantly affecting the dynamic range that adds impact to digital television audio. [6] When used in combination with a meter capable of measuring loudness by the ITU-R BS.1770 standard (or derivatives of this standard, such as EBU R128) U.S. broadcasters will be able to achieve CALM compliance by effectively managing and monitoring audio levels.

Linear Acoustic also manufacturers the UPMAX 5.1-channel upmixer, which creates multi-channel surround sound audio from 2-channel (stereo) sources. NBC utilized this product during the 2008 Beijing Summer Olympics, [7] and relied upon the companys AERO.qc products during the 2010 Vancouver Winter Olympics. [8]

In 2008, Linear Acoustic became part of The Telos Alliance, based in Cleveland, Ohio. The Telos Alliance comprises Telos Systems, Axia Audio, Omnia Audio, and 25-Seven Systems that manufacture broadcast telephone systems, consoles and audio over IP gear, audio processors, and audio time management hardware for radio stations. Frank Foti, founder of Omnia Audio, is The Telos Alliance CEO.

At the 2012 NAB Show in Las Vegas, Linear Acoustic announced a co-branding agreement with Dolby Laboratories under which the company will manufacture stand-alone Dolby-centric professional products such as audio codecs and audio bitstream test tools. [9]

Awards

In 2011, Linear Acoustic received a Technical Emmy for The Pioneering Development of an Audio/Metadata Processor for Conforming Audio to the ATSC Standard. [10]

Related Research Articles

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A Dolby noise-reduction system, or Dolby NR, is one of a series of noise reduction systems developed by Dolby Laboratories for use in analog audio tape recording. The first was Dolby A, a professional broadband noise reduction system for recording studios in 1965, but the best-known is Dolby B, a sliding band system for the consumer market, which helped make high fidelity practical on cassette tapes, which used a relatively noisy tape size and speed. It is common on high-fidelity stereo tape players and recorders to the present day, although Dolby has as of 2016 ceased licensing the technology for new cassette decks. Of the noise reduction systems, Dolby A and Dolby SR were developed for professional use. Dolby B, C, and S were designed for the consumer market. Aside from Dolby HX, all the Dolby variants work by companding: compressing the dynamic range of the sound during recording, and expanding it during playback.

<span class="mw-page-title-main">Freeview (UK)</span> British digital terrestrial television platform

Freeview is the United Kingdom's sole digital terrestrial television platform. It is operated by Everyone TV and DTV Services Ltd, a joint venture between the BBC, ITV, Channel 4, Channel 5 and Sky. It was launched on 30 October 2002, taking over the licence from ITV Digital which collapsed that year. The service provides consumer access via an aerial to the seven DTT multiplexes covering the United Kingdom. As of July 2020, it has 85 TV channels, 26 digital radio channels, 10 HD channels, six text services, 11 streamed channels, and one interactive channel.

<span class="mw-page-title-main">DVB</span> Open standard for digital television broadcasting

Digital Video Broadcasting (DVB) is a set of international open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium, and are published by a Joint Technical Committee (JTC) of the European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU).

<span class="mw-page-title-main">Home cinema</span> Home entertainment system that aims to replicate the experience of a movie theater

Home cinema, also called home theaters or theater rooms, are home entertainment audio-visual systems that seek to reproduce a movie theater experience and mood using consumer electronics-grade video and audio equipment that is set up in a room or backyard of a private home. Some studies show that films are rated better and generate more intense emotions when watched in a movie theater, but convenience is a major appeal for home cinemas. In the 1980s, home cinemas typically consisted of a movie pre-recorded on a LaserDisc or VHS tape; a LaserDisc Player or VCR; and a heavy, bulky large-screen cathode ray tube TV set, although sometimes CRT projectors were used instead. In the 2000s, technological innovations in sound systems, video player equipment and TV screens and video projectors have changed the equipment used in home cinema set-ups and enabled home users to experience a higher-resolution screen image, improved sound quality and components that offer users more options. The development of Internet-based subscription services means that 2020s-era home theatre users do not have to commute to a video rental store as was common in the 1980s and 1990s.

<span class="mw-page-title-main">Surround sound</span> System with loudspeakers that surround the listener

Surround sound is a technique for enriching the fidelity and depth of sound reproduction by using multiple audio channels from speakers that surround the listener. Its first application was in movie theaters. Prior to surround sound, theater sound systems commonly had three screen channels of sound that played from three loudspeakers located in front of the audience. Surround sound adds one or more channels from loudspeakers to the side or behind the listener that are able to create the sensation of sound coming from any horizontal direction around the listener.

<span class="mw-page-title-main">Dynamic range compression</span> Audio signal processing operation

Dynamic range compression (DRC) or simply compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, thus reducing or compressing an audio signal's dynamic range. Compression is commonly used in sound recording and reproduction, broadcasting, live sound reinforcement and some instrument amplifiers.

dbx (noise reduction) Family of noise reduction systems

dbx is a family of noise reduction systems developed by the company of the same name. The most common implementations are dbx Type I and dbx Type II for analog tape recording and, less commonly, vinyl LPs. A separate implementation, known as dbx-TV, is part of the MTS system used to provide stereo sound to North American and certain other TV systems. The company, dbx, Inc., was also involved with Dynamic Noise Reduction (DNR) systems.

<span class="mw-page-title-main">Dolby</span> Audio technology company

Dolby Laboratories, Inc. is a British-American technology corporation specializing in audio noise reduction, audio encoding/compression, spatial audio, and HDR imaging. Dolby licenses its technologies to consumer electronics manufacturers.

<span class="mw-page-title-main">Loudness</span> Subjective perception of sound pressure

In acoustics, loudness is the subjective perception of sound pressure. More formally, it is defined as the "attribute of auditory sensation in terms of which sounds can be ordered on a scale extending from quiet to loud". The relation of physical attributes of sound to perceived loudness consists of physical, physiological and psychological components. The study of apparent loudness is included in the topic of psychoacoustics and employs methods of psychophysics.

<span class="mw-page-title-main">DTS (company)</span> Series of multichannel audio technologies

DTS, Inc. is an American company. DTS company makes multichannel audio technologies for film and video. Based in Calabasas, California, the company introduced its DTS technology in 1993 as a competitor to Dolby Laboratories, incorporating DTS in the film Jurassic Park (1993). The DTS product is used in surround sound formats for both commercial/theatrical and consumer-grade applications. It was known as The Digital Experience until 1995. DTS licenses its technologies to consumer electronics manufacturers.

Dolby Digital Plus, also known as Enhanced AC-3, is a digital audio compression scheme developed by Dolby Labs for the transport and storage of multi-channel digital audio. It is a successor to Dolby Digital (AC-3), and has a number of improvements over that codec, including support for a wider range of data rates, an increased channel count, and multi-program support, as well as additional tools (algorithms) for representing compressed data and counteracting artifacts. Whereas Dolby Digital (AC-3) supports up to five full-bandwidth audio channels at a maximum bitrate of 640 kbit/s, E-AC-3 supports up to 15 full-bandwidth audio channels at a maximum bitrate of 6.144 Mbit/s.

The Technology and Engineering Emmy Awards, or Technology and Engineering Emmys, are one of two sets of Emmy Awards that are presented for outstanding achievement in engineering development in the television industry. The Technology and Engineering Emmy Awards are presented by the National Academy of Television Arts and Sciences (NATAS), while the separate Primetime Engineering Emmy Awards are given by its sister organization the Academy of Television Arts & Sciences (ATAS).

MPEG Multichannel, also known as MPEG-2 Backwards Compatible, or MPEG-2 BC, is an extension to the MPEG-1 Layer II audio compression specification, as defined in the MPEG-2 Audio standard which allows it provide up to 5.1-channels of audio. To maintain backwards compatibility with the older 2-channel (stereo) audio specification, it uses a channel matrixing scheme, where the additional channels are mixed into the two backwards compatible channels. Extra information in the data stream contains signals to process extra channels from the matrix.

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The Commercial Advertisement Loudness Mitigation Act requires the U.S. Federal Communications Commission to bar the audio of TV commercials from being broadcast louder than the TV program material they accompany by requiring all "multichannel video programming" distributors to implement the "Techniques for Establishing and Maintaining Audio Loudness for Digital Television" issued by the international industry group Advanced Television Systems Committee. The final bill was passed on September 29, 2010.

EBU R 128 is a recommendation for loudness normalisation and maximum level of audio signals. It is primarily followed during audio mixing of television and radio programmes and adopted by broadcasters to measure and control programme loudness. It was first issued by the European Broadcasting Union in August 2010 and most recently revised in August 2020.

Loudness, K-weighted, relative to full scale (LKFS) is a standard loudness measurement unit used for audio normalization in broadcast television systems and other video and music streaming services.

The Digital Production Partnership (DPP) is an initiative formed jointly by the UK's public service broadcasters to help producers and broadcasters maximise the potential benefits of digital television production.

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References

  1. "DTSAC3". Archived from the original on 2010-02-27. Retrieved 2010-03-14. Retrieved April 11, 2013
  2. broadcastengineering.com http://broadcastengineering.com/blog/linear-acoustic-founder-tim-carroll-share-expert-perspective-loudness-control-listener-fatigue- . Retrieved April 11, 2013.{{cite web}}: Missing or empty |title= (help)[ title missing ]
  3. LA Times CALM Act: Reducing TV commercial volume was a feat http://articles.latimes.com/2012/dec/13/entertainment/la-et-ct-calm-act-an-engineering-feat-20121213 Retrieved April 11, 2013
  4. What’s up with obnoxiously loud TV shows and commercials? June 1, 2012 Retrieved April 11, 2013 http://www.straightdope.com/columns/read/3055/what-s-up-with-obnoxiously-loud-tv-shows-and-commercials
  5. Eshoo, Whitehouse & Industry Leaders Trumpet New Law to Stop High Volume Commercials Dec. 13 2012 http://eshoo.house.gov/index.php?option=com_content&task=view&id=1294&Itemid=100067 Retrieved April 11, 2013
  6. Linear Acoustic AERO
  7. Linear Acoustic to Provide UPMAX:neo(TM) 5.1 Channel Upmixer, June 23, 2008, retrieved April 11, 2013
  8. "Linear Acoustic Provides AERO.qc Audio Quality Controllers For NBC's Coverage Of The Vancouver Winter Games", Broadcast Engineering, March 12, 2010, retrieved April 11, 2013
  9. "Linear Acoustic and Dolby Expand Partnership", NAB Daily News, April 17, 2012, retrieved April 16, 2013
  10. "Linear Acoustic honored with Technical EMMY for real-time audio/metadata processor", Broadcast Engineering, February 3, 2011, retrieved April 11, 2013