TOSLINK

Last updated

TOSLINK / EIAJ optical
TOS LINK clear cable.jpg
Clear TOSLINK cable with a round connector for S/PDIF connectivity.
Type Optical digital audio connector
Production history
Designer Toshiba
Designed 1983
Manufacturer Toshiba
Produced Since 1983
General specifications
Hot pluggable Yes
External Yes
Audio signal S/PDIF bitstream. Originally limited to 48 kHz at 20 bits PCM. Extended by manufacturers to support additional formats.[ citation needed ]
Cable Optical fiber, ~10 m (33 ft) maximum [1]
Pins 1
Connector JIS F05 (JIS C5974-1993 F05)
Data
Width Serial
Bitrate
  • 3.1 Mbit/s (S/PDIF, 48 kHz PCM) [1]
  • 15 Mbit/s (common TORX147 receiver)
  • 125 Mbit/s (automotive, 2003) [2]
Max. devices 1
Protocol Serial

TOSLINK (Toshiba Link) [3] is a standardized [4] optical fiber connector system. [5] Generically known as optical audio, the most common use of the TOSLINK optical fiber connector is in consumer audio equipment in which the digital optical socket carries (transmits) a stream of digital audio signals from audio equipment (CD player, DVD player, Digital Audio Tape recorder, computer, video game console) to an AV receiver that can decode two channels of uncompressed, pulse-code modulated (PCM) audio; or decode compressed 5.1/7.1 surround sound audio signals, such as Dolby Digital and DTS. Unlike an HDMI connector cable, a TOSLINK optical fiber connector does not possess the bandwidth capacity to carry the uncompressed audio signals of Dolby TrueHD and of DTS-HD Master Audio; nor carry more than two channels of PCM audio.

Contents

Although the TOSLINK connector supports several media formats and physical standards, the most common digital audio connectors are the rectangular EIAJ/JEITA RC-5720 (also CP-1201 and JIS C5974-1993 F05). [6] In a TOSLINK connector, the optical signal appears as a red light, with a peak wavelength of 650 nm. [3] Depending on the type of modulated signal being carried, other optical wavelengths can be present. [6]

History

Toshiba originally created TOSLINK to connect their CD players to the receivers they manufactured, for PCM audio streams. The data-link layer is based on the Sony/Philips Digital Interface [7] [8] (S/PDIF), while the hardware layer utilizes a fiber optic transmission system, rather than the electrical (copper) hardware layer of S/PDIF. TOSLINK was soon adopted by manufacturers of most CD players. It can often be found on video source (DVD and Blu-ray players, cable boxes and game consoles) to connect the digital audio stream to Dolby Digital/DTS decoders.

TOSLINK connector (JIS F05) TOSLINK.jpg
TOSLINK connector (JIS F05)

Although the generic name for the connector is the EIAJ optical, the trade name TOSLINK is a registered trademark of the Toshiba electronics company, derived from TOShiba-LINK; other etymologic variations were the words TOSlink, TosLink, and Tos-link.[ citation needed ]

The ADAT Lightpipe (ADAT Optical) uses an optical transmission system similar to that of the TOSLINK connector used in the professional recording of music and in the audio component industry. The ADAT Lightpipe connector format uses the same JIS F05 connectors as the TOSLINK connector, the ADAT Lightpipe data format is incompatible with S/PDIF.[ citation needed ]

Properties and problems

Due to their high attenuation of light, the effective range of plastic optical cables is limited to 5–10 m. [1] They can temporarily fail or be permanently damaged if tightly bent. Although less commonly available and more expensive than plastic optical fiber (POF) cables, glass or silica optical fibers have lower losses and can extend the range of the TOSLINK system.

Optical cables are not susceptible to electrical problems such as ground loops and RF interference. [9]

Design

A TOSLINK fiber optic audio cable being illuminated by a laser on the left end Fiber optic illuminated.jpg
A TOSLINK fiber optic audio cable being illuminated by a laser on the left end

Several types of fiber can be used for TOSLINK: inexpensive 1 mm plastic optical fiber, higher-quality multistrand plastic optical fibers, or quartz glass optical fibers, depending on the desired bandwidth and application. TOSLINK cables are usually limited to 5 meters in length, with a technical maximum [1] of 10 meters, for reliable transmission without the use of a signal booster or a repeater. However, it is very common for interfaces on newer consumer electronics (satellite receivers and PCs with optical outputs) to easily run over 30 meters on even low-cost (0.82 USD/m 2009) TOSLINK cables. TOSLINK transmitters operate at a nominal optical wavelength of 650 nm.

A mini-TOSLINK adapter Minitoslink.png
A mini-TOSLINK adapter

Mini-TOSLINK is a standardized [4] optical fiber connector smaller than the standard square TOSLINK connector commonly used in larger consumer audio equipment. The plug is almost the same size and shape as the ubiquitous 3.5 mm stereo minijack. Adapters are available to connect a full-size TOSLINK plug to a mini-TOSLINK socket. Combined 3.5 mm jack and mini-TOSLINK sockets exist which can accept a 3.5 mm or mini-TOSLINK plug; mini-TOSLINK plugs and sockets are made 0.5 mm longer than electrical jack plugs so that the latter are too short to touch and damage the LED of a mini-TOSLINK capable socket. Many discontinued laptop computer and portable digital audio equipment models, such as the Google Chromecast Audio device, [10] [11] Apple AirPort Express, and iPod Hi-Fi, as well as some MiniDisc recorders, [12] use these connectors that allow for the insertion of 3.5 mm analog (electrical) headphone output, microphone input, or mini-TOSLINK digital (optical) output (or input, in the case of MiniDisc recorders).

Related Research Articles

<span class="mw-page-title-main">SCART</span> 21-pin connector for audio-visual equipment

SCART is a French-originated standard and associated 21-pin connector for connecting audio-visual (AV) equipment. The name SCART comes from Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs, "Radio and Television Receiver Manufacturers' Association", the French organisation that created the connector in the mid-1970s. The related European standard EN 50049 was refined and published in 1978 by CENELEC, calling it péritelevision, but it is commonly called by the abbreviation péritel in French.

Dolby Digital, originally synonymous with Dolby AC-3, is the name for a family of audio compression technologies developed by Dolby Laboratories. Called Dolby Stereo Digital until 1995, it is lossy compression. The first use of Dolby Digital was to provide digital sound in cinemas from 35 mm film prints. It has since also been used for TV broadcast, radio broadcast via satellite, digital video streaming, DVDs, Blu-ray discs and game consoles.

<span class="mw-page-title-main">S/PDIF</span> Standardized digital audio interface

S/PDIF is a type of digital audio interface used in consumer audio equipment to output audio over relatively short distances. The signal is transmitted over either a coaxial cable using RCA or BNC connectors, or a fibre-optic cable using TOSLINK connectors. S/PDIF interconnects components in home theaters and other digital high-fidelity systems.

<span class="mw-page-title-main">RCA connector</span> Electrical connector used for analog audio and video

The RCA connector is a type of electrical connector commonly used to carry audio and video signals. The name RCA derives from the company Radio Corporation of America, which introduced the design in the 1930s. The connector’s male plug and female jack are called RCA plug and RCA jack.

A DVD player is a machine that plays DVDs produced under both the DVD-Video and DVD-Audio technical standards, two different and incompatible standards. Some DVD players will also play audio CDs. DVD players are connected to a television to watch the DVD content, which could be a movie, a recorded TV show, or other content.

<span class="mw-page-title-main">DVD-Audio</span> DVD format for storing high-fidelity audio

DVD-Audio is a digital format for delivering high-fidelity audio content on a DVD. DVD-Audio uses most of the storage on the disc for high-quality audio and is not intended to be a video delivery format.

<span class="mw-page-title-main">Phone connector (audio)</span> Family of connectors typically used for analog signals

A phone connector is a family of cylindrically-shaped electrical connectors primarily for analog audio signals. Invented in the late 19th century for telephone switchboards, the phone connector remains in use for interfacing wired audio equipment, such as headphones, speakers, microphones, mixing consoles, and electronic musical instruments. A male connector, is mated into a female connector, though other terminology is used.

<span class="mw-page-title-main">DIN connector</span> Electrical connector

The DIN connector is an electrical connector that was standardized by the Deutsches Institut für Normung (DIN), the German Institute for Standards, in the mid 1950s, initially with 3 pins for mono, but when stereo connections and gear appeared in late 1950s, versions with 5 pins or more were launched. The male DIN connectors (plugs) feature a 13.2 mm diameter metal shield with a notch that limits the orientation in which plug and socket can mate. The range of DIN connectors, different only in the configuration of the pins, have been standardized as DIN 41524 / IEC/DIN EN 60130-9 ; DIN 45322 ; DIN 45329 / IEC/DIN EN 60130–9 ; and DIN 45326 / IEC/DIN EN 60130-9.

<span class="mw-page-title-main">DTS, Inc.</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.

<span class="mw-page-title-main">Patch cable</span> Cable used to connect electronic or optical devices

A patch cable, patch cord or patch lead is an electrical or fiber-optic cable used to connect one electronic or optical device to another for signal routing. Devices of different types are connected with patch cords.

Dolby TrueHD is a lossless, multi-channel audio codec developed by Dolby Laboratories for home video, used principally in Blu-ray Disc and compatible hardware. Dolby TrueHD, along with Dolby Digital Plus (E-AC-3) and Dolby AC-4, is one of the intended successors to the Dolby Digital (AC-3) lossy surround format. Dolby TrueHD competes with DTS's DTS-HD Master Audio, another lossless surround sound codec.

<span class="mw-page-title-main">Sony BDP-S1</span>

The Sony BDP-S1 is a first generation Blu-ray Disc (BD) player and is the first such player released in North America. It was originally scheduled for release in the United States on August 18, 2006 with a MSRP of $999.95. Sony had postponed the release date of this player several times and it was released on December 4, 2006.

<span class="mw-page-title-main">AV receiver</span> Consumer electronics component

An audio/video receiver (AVR) or a stereo receiver is a consumer electronics component used in a home theater or hi-fi system. Its purpose is to receive audio and video signals from a number of sources, and to process them and provide power amplifiers to drive loudspeakers, and/or route the video to displays such as a television, monitor or video projector. Inputs may come from a TV, FM, or AM tuner, satellite receiver, DVD players, Blu-ray Disc players, VCRs or video game consoles, among others. The AVR source selection and settings such as volume, are typically set by a remote controller.

<span class="mw-page-title-main">MADI</span> Multichannel digital audio interface

Multichannel Audio Digital Interface (MADI) standardized as AES10 by the Audio Engineering Society (AES) defines the data format and electrical characteristics of an interface that carries multiple channels of digital audio. The AES first documented the MADI standard in AES10-1991 and updated it in AES10-2003 and AES10-2008. The MADI standard includes a bit-level description and has features in common with the two-channel AES3 interface.

<span class="mw-page-title-main">DTS-HD Master Audio</span> Lossless audio codec for home theater

DTS-HD Master Audio is a multi-channel, lossless audio codec developed by DTS as an extension of the lossy DTS Coherent Acoustics codec. Rather than being an entirely new coding mechanism, DTS-HD MA encodes an audio master in lossy DTS first, then stores a concurrent stream of supplementary data representing whatever the DTS encoder discarded. This gives DTS-HD MA a lossy "core" able to be played back by devices that cannot decode the more complex lossless audio. DTS-HD MA's primary application is audio storage and playback for Blu-ray Disc media; it competes in this respect with Dolby TrueHD, another lossless surround format.

The ADAT Lightpipe, officially the ADAT Optical Interface, is a standard for the transfer of digital audio between equipment. It was originally developed by Alesis but has since become widely accepted, with many third party hardware manufacturers including Lightpipe interfaces on their equipment. The protocol has become so popular that the term ADAT is now often used to refer to the transfer standard rather than to the Alesis Digital Audio Tape itself.

Founded in 1948, the Electronic Industries Association of Japan (EIAJ) was one of two Japanese electronics trade organizations that were merged into the Japan Electronics and Information Technology Industries Association (JEITA).

An audio signal is a representation of sound, typically using either a changing level of electrical voltage for analog signals, or a series of binary numbers for digital signals. Audio signals have frequencies in the audio frequency range of roughly 20 to 20,000 Hz, which corresponds to the lower and upper limits of human hearing. Audio signals may be synthesized directly, or may originate at a transducer such as a microphone, musical instrument pickup, phonograph cartridge, or tape head. Loudspeakers or headphones convert an electrical audio signal back into sound.

Audio connectors and video connectors are electrical or optical connectors for carrying audio or video signals. Audio interfaces or video interfaces define physical parameters and interpretation of signals. For digital audio and digital video, this can be thought of as defining the physical layer, data link layer, and most or all of the application layer. For analog audio and analog video these functions are all represented in a single signal specification like NTSC or the direct speaker-driving signal of analog audio.

References

  1. 1 2 3 4 "SPDIF". epanorama.net. Retrieved 13 February 2022.
  2. "New Fiber Optic Devices in Toshiba's TOSLINK Line-up Supports Development of High-speed Automotive LAN". Toshiba. 20 February 2003.
  3. 1 2 "Toshiba TOTX1701 TOSLINK Transmitter Module specifications". Archived from the original on 17 July 2011.
  4. 1 2 "EIAJ RC-5720C". www.jeita.or.jp. Retrieved 28 July 2024.
  5. 1 2 "Product guide, Fiber-Optic Devices TOSLINK(tm)" (PDF). 100621 digikey.com
  6. "S/PDIF Information". Intel. 21 July 2017. Retrieved 3 April 2018.
  7. "S/PDIF". PCMag Encyclopedia. Retrieved 13 February 2022.
  8. Joseph D. Cornwall (31 December 2004). "Understanding Digital Interconnects". Audioholics.com. Retrieved 12 July 2007.
  9. Pendlebury, Ty (10 December 2015). "Chromecast Audio adds support for multiroom music and high-res files". Cnet . Archived from the original on 21 December 2021.
  10. Greenwald, Will (14 December 2015). "Google Chromecast Audio". PC Magazine . Archived from the original on 4 October 2015.
  11. "Portable MiniDisc Recorder: Operating instructions, MD Walkman MZ-R55" (PDF). Sony Corporation. 1998. pp. 10–11.