Soundstream Technical Specifications
Frequency Response Frequency response Frequency response is the quantitative measure of the output spectrum of a system or device in response to a stimulus, and is used to characterize the dynamics of the system. It is a measure of magnitude and phase of the output as a function of frequency, in comparison to the input...	Flat from 0Hz to 21kHz
Wow and Flutter Wow and Flutter Wow and Flutter is an EP by the post-rock band Stereolab, released in 1994. A limited edition of 3000 7" copies was released with hand-painted covers. Two of the tracks appear on Mars Audiac Quintet, which was released the same year.-Track listing:...	Unmeasurable
Total Harmonic Distortion Total harmonic distortion The total harmonic distortion, or THD, of a signal is a measurement of the harmonic distortion present and is defined as the ratio of the sum of the powers of all harmonic components to the power of the fundamental frequency...	Less than 0.004% at 0VU VU meter A VU meter is often included in audio equipment to display a signal level in Volume Units; the device is sometimes also called volume indicator ....
Signal-to-Noise Ratio Signal-to-noise ratio Signal-to-noise ratio is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. It is defined as the ratio of signal power to the noise power. A ratio higher than 1:1 indicates more signal than noise...	Better than 90dB Decibel The decibel is a logarithmic unit that indicates the ratio of a physical quantity relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities...  RMS Root mean square In mathematics, the root mean square , also known as the quadratic mean, is a statistical measure of the magnitude of a varying quantity. It is especially useful when variates are positive and negative, e.g., sinusoids... , Unweighted
Dynamic Range Dynamic range Dynamic range, abbreviated DR or DNR, is the ratio between the largest and smallest possible values of a changeable quantity, such as in sound and light. It is measured as a ratio, or as a base-10 or base-2 logarithmic value.-Dynamic range and human perception:The human senses of sight and...	Better than 90dB RMS, Unweighted
Crosstalk	Less than -85dB
Print-through Print-through Print-through is a generally undesirable effect that arises in the use of magnetic tape for storing analogue information, in particular music....	None
Sampling Rate Sampling rate The sampling rate, sample rate, or sampling frequency defines the number of samples per unit of time taken from a continuous signal to make a discrete signal. For time-domain signals, the unit for sampling rate is hertz , sometimes noted as Sa/s...	50,000 per second
Digital Format	16 bits linear encoding / decoding

The Company

Soundstream Inc. was founded in 1975 in Salt Lake City, Utah

Salt Lake City, Utah

Salt Lake City is the capital and the most populous city of the U.S. state of Utah. The name of the city is often shortened to Salt Lake or SLC. With a population of 186,440 as of the 2010 Census, the city lies in the Salt Lake City metropolitan area, which has a total population of 1,124,197...

 by Dr. Thomas G. Stockham, Jr

Thomas Stockham

Thomas Greenway Stockham was an American scientist who developed the first practical digital audio recording system, and pioneered techniques for digital audio recording and processing as well....

. It was the world’s first audiophile

Audiophile

An audiophile is a person who enjoys listening to recorded music, usually in a home. Some audiophiles are more interested in collecting and listening to music, while others are more interested in collecting and listening to audio components, whose "sound quality" they consider as important as the...

 digital audio

Digital audio

Digital audio is sound reproduction using pulse-code modulation and digital signals. Digital audio systems include analog-to-digital conversion , digital-to-analog conversion , digital storage, processing and transmission components...

 recording company, providing commercial services for recording and computer-based editing. Soundstream provided worldwide on-location recording services to Telarc, Delos

Delos International

Delos International is an American record label. Based in Hollywood, California, it specializes in publishing classical music. The Delos recording label was founded in 1973 by Amelia S. Haygood , one of the most prominent figures in the classical recording industry...

, RCA

RCA

RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...

, Philips

Philips

Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

, Vanguard

Vanguard Records

Vanguard Records is a record label set up in 1950 by brothers Maynard and Seymour Solomon in New York. It started as a classical label, but is perhaps best known for its catalogue of recordings by a number of pivotal folk and blues artists from the 1960s; the Bach Guild was a subsidiary...

, Varèse Sarabande

Varèse Sarabande

Varèse Sarabande is an American record label, distributed by Universal Music Group, which specializes in film scores and original cast recordings. It aims to reissue rare or unavailable albums as well as newer releases by artists no longer under a contract...

, Angel

Angel Records

Angel Records is a record label belonging to EMI. It was formed in 1953 and specialised in classical music, but included an occasional operetta or Broadway score...

, Warner Brothers, CBS

CBS

CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...

, Decca

Decca Records

Decca Records began as a British record label established in 1929 by Edward Lewis. Its U.S. label was established in late 1934; however, owing to World War II, the link with the British company was broken for several decades....

, Chalfont

Chalfont Records

Chalfont Records was an American record label associated with Varèse Sarabande.Chalfont made recordings of the London Symphony Orchestra, the National Symphony Orchestra, the Royal Liverpool Philharmonic, Noel Rawsthorne, and Carlo Curley...

, and other labels. It also leased or sold some recorders (a total of 18 were manufactured). Although most recordings were of classical music, the range included country

Country music

Country music is a popular American musical style that began in the rural Southern United States in the 1920s. It takes its roots from Western cowboy and folk music...

, rock

Rock music

Rock music is a genre of popular music that developed during and after the 1960s, particularly in the United Kingdom and the United States. It has its roots in 1940s and 1950s rock and roll, itself heavily influenced by rhythm and blues and country music...

, jazz

Jazz

Jazz is a musical style that originated at the beginning of the 20th century in African American communities in the Southern United States. It was born out of a mix of African and European music traditions. From its early development until the present, jazz has incorporated music from 19th and 20th...

, pop

Pop music

Pop music is usually understood to be commercially recorded music, often oriented toward a youth market, usually consisting of relatively short, simple songs utilizing technological innovations to produce new variations on existing themes.- Definitions :David Hatch and Stephen Millward define pop...

, and avant-garde

Avant-garde music

Avant-garde music is a term used to characterize music which is thought to be ahead of its time, i.e. containing innovative elements or fusing different genres....

.

The first digital recording of a symphony orchestra was made in 1976 by Soundstream's prototype 37kHz, 16-bit, two channel recorder. New World Records

New World Records

New World Records is a record label based in New York City specialising in American music. The label was established in 1975 through a Rockefeller Foundation grant to produce a 100 disc anthology covering 200 years of American music....

, which recorded the Santa Fe Opera's

Santa Fe Opera

The Santa Fe Opera is an American opera company, located north of Santa Fe in the U.S. state of New Mexico, headquartered on a former guest ranch of .-General history:...

 performance of Virgil Thomson's

Virgil Thomson

Virgil Thomson was an American composer and critic. He was instrumental in the development of the "American Sound" in classical music...

 The Mother of Us All, provided Soundstream with a stereo feed from their multitrack console. Soundstream demonstrated its recording of the opera at the Fall 1976 AES Convention. Critiques of the recording, most notably from Telarc's Jack Renner

Jack Renner (recording engineer)

Jack L. Renner is an American classically trained musician and recording engineer, best known as chairman, CEO and chief recording engineer of the Telarc International Corporation....

 and Robert Woods, led directly to the improved 4-channel, 50kHz sample rate recorder that was used for all of Soundstream's future commercial releases. The New World Records issue of Mother of Us All was not from the digital recording made by Soundstream.

Also in 1976, Soundstream restored acoustic (pre-electronic) recordings of Enrico Caruso, by digitizing the recordings on a computer, and processing them using a technique called 'blind deconvolution

Deconvolution

In mathematics, deconvolution is an algorithm-based process used to reverse the effects of convolution on recorded data. The concept of deconvolution is widely used in the techniques of signal processing and image processing...

'. These were released by RCA Records

RCA Records

RCA Records is one of the flagship labels of Sony Music Entertainment. The RCA initials stand for Radio Corporation of America , which was the parent corporation from 1929 to 1985 and a partner from 1985 to 1986.RCA's Canadian unit is Sony's oldest label...

 as "Caruso - A Legendary Performer". In subsequent years Soundstream restored most of the RCA Caruso catalog, as well as some RCA recordings by Irish tenor John McCormack

John McCormack

John Count McCormack, in full, John Francis Count McCormack was a world-famous Irish tenor singer, celebrated for his performances of the operatic and popular song repertoires, and renowned for his diction and breath control...

.

Soundstream’s first commercially released recording (popular music on the Orinda label) in 1978 was a month shy of the world’s first digitally recorded commercial release

Bop till You Drop

Bop till You Drop is Ry Cooder's ninth album, released in 1979 . This was the first major-label digitally recorded album of Pop music...

. For the ensuing three years, 50% of all classical music recorded digitally used Soundstream equipment.

Unlike its competitors, Soundstream's analog circuitry was transformerless, permitting a frequency response to 0Hz

Hertz

The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....

 (DC

Direct current

Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...

). This accounted for the ‘bass drum heard round the world’ review of the 1978 Telarc recording of Frederick Fennell: The Cleveland Symphonic Winds. Soundstream collaborated with Telarc for several years, producing legendary symphonic recordings; the earliest ones are chronicled in Renner. The care with which Telarc selected and used its microphones and audio console, combined with the Soundstream recorder, created a gold standard for audiophile recording. Telarc has re-released many of its original Soundstream recordings in SACD format, with a DSD-equivalent

Direct Stream Digital

Direct-Stream Digital is the trademark name used by Sony and Philips for their system of recreating audible signals which uses pulse-density modulation encoding, a technology to store audio signals on digital storage media which is used for the Super Audio CD .The signal is stored as delta-sigma...

 sampling rate of 50 kHz.

Soundstream recordings made before the advent of the CD

Compact Disc

The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...

 were released as high-quality vinyl LP albums

Gramophone record

A gramophone record, commonly known as a phonograph record , vinyl record , or colloquially, a record, is an analog sound storage medium consisting of a flat disc with an inscribed, modulated spiral groove...

. Despite analog playback, many of these releases were sufficiently impressive to gain an early acceptance for digital audio. The recording industry’s transition to digital was further facilitated by the many demonstrations given by Dr. Stockham, whose articulate explanations of digital audio theory and practice were renowned.

In 1980, Digital Recording Corporation (DRC) acquired Soundstream. DRC attempted to develop a home digital player that would use a photographically reproducible ‘optical card’ as opposed to the mechanically pressed CD. This effort was eclipsed by the rise of the CD, leading to the company’s demise in 1985.

The Technology

The company developed its four-channel recorder in 1977. The Soundstream Digital Tape Recorder (DTR) consisted of a modified Honeywell

Honeywell

Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....

 5600E instrumentation transport

Transport (recording)

A transport is a device that handles a particular physical storage medium itself, and extracts or records the information to and from the medium, to an outboard set of processing electronics that the transport is connected to.A transport houses no electronics itself for encoding and decoding the...

 and analog and digital

Digital

A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...

 circuitry designed and built by Soundstream.

The Digital Tape Recorder

The Digital Tape Recorder was a portable four-channel digital audio processor containing the analog to digital converters, tape-data recovery and clock generation circuits, and the digital to analog converters. External hardware (tape drive, editing system, and digital delay unit) connected to the DTR through connectors on the back panel. The unit measured 20"x18"x10" and weighed 67 pounds.

Analog signals entered the DTR through standard XLR connectors at the rear of the unit. There, a differential input amplifier routed the signal through the front panel attenuation fader to the input low-pass (anti-alias) filter.

The filtered analog signal passed through a custom sample and hold

Sample and hold

In electronics, a sample and hold circuit is an analog device that samples the voltage of a continuously varying analog signal and holds its value at a constant level for a specified minimal period of time. Sample and hold circuits and related peak detectors are the elementary analog memory...

 and was digitized by an Analogic

Analogic Corporation

Analogic is an American multinational corporation. Analogic Corporation currently employs 1,200 employees worldwide with approximately 400 working at the main facility and headquarters in Peabody, Massachusetts.-History:...

 MP8016 16-bit Analog-to-Digital Converter operating at a 50kHz sample rate. A 3-bit sync pattern and an even-parity bit were added to each 16-bit sample to form a 20-bit word that was serialized and transmitted by interface electronics to the tape transport where each audio channel's data were written to two separate tape tracks.

During tape playback or while recording and monitoring from tape, the redundant tracks of recorded data from the transport were sent to data recovery circuitry. Because the data recorded on tape are necessarily bandwidth-limited, the data-recovery circuitry squared-up the data signals and then created clocks to match the incoming data streams. Additional circuitry located word boundaries and converted the data to parallel format. In the event of tape dropouts, an error-avoidance scheme selected the unaffected track's data.

The selected data were then clocked into an Analogic MP1926A Digital-to-Analog Converter at the original crystal-controlled sample rate. The analog signal from the converter was routed to the output low-pass (reconstruction) filter. Voltage and current gain sufficient for +20dBm

DBm

dBm is an abbreviation for the power ratio in decibels of the measured power referenced to one milliwatt . It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form...

 into 150 ohms was provided by the output-buffer amplifier which signal was then output at the XLR connector on the DTR's rear panel.

The Honeywell Tapedeck (or Honeywell Transport)

Soundstream-modified Honeywell 5600e Instrumentation Tape Drives (HTD) used custom high-frequency 18-track record and playback heads. The two outer tracks were reserved for ancillary data - SMPTE time code

SMPTE time code

SMPTE timecode is a set of cooperating standards to label individual frames of video or film with a time code defined by the Society of Motion Picture and Television Engineers in the SMPTE 12M specification...

 and the like. The remaining sixteen tracks were used to record up to eight channels of digital audio - two redundant tracks for each audio channel. The two tracks in a redundant track pair were separated as widely as possible to minimize playback errors due to tape defects (dropouts) - audio channel one was recorded on tracks 1 and 9.

At the front of the HTD, Soundstream installed Track Selector hardware. The left side selector allowed the operator to choose which audio channel pair (1,2; 3,4) was assigned to which tape track pair (1,2; 3,4; 5,6; or 7,8). The right side selector controlled the application of record circuitry power for each of the eight tracks.

The HTD initially used 1" Ampex

Ampex

Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...

 460 reel-to-reel tape at 35ips. Later, Soundstream switched to Ampex 466 tape which allowed for the slower tape speed of 30ips.

The Digital Editing System

Soundstream’s digital editing system was the first instance of a computer used to edit commercial recordings. It consisted of a Digital Equipment

Digital Equipment Corporation

Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

 PDP 11/60

PDP-11

The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...

 computer, Soundstream’s interface (the Digital Audio Interface) to transfer data between its recorder and the computer’s disks (a pair of Braegen 14" disk drives), digital-to-analog playback hardware, and editing software. For all intents and purposes, this system was the very first digital audio workstation

Digital audio workstation

A digital audio workstation is an electronic system designed solely or primarily for recording, editing and playing back digital audio. DAWs were originally tape-less, microprocessor-based systems such as the Synclavier and Fairlight CMI...

. In addition to its own facility, Soundstream installed editing systems at Paramount Pictures

Paramount Pictures

Paramount Pictures Corporation is an American film production and distribution company, located at 5555 Melrose Avenue in Hollywood. Founded in 1912 and currently owned by media conglomerate Viacom, it is America's oldest existing film studio; it is also the last major film studio still...

 (Hollywood), RCA (New York), and Bertelsmann

Bertelsmann

Bertelsmann AG is a multinational media corporation founded in 1835, based in Gütersloh, Germany. The company operates in 63 countries and employs 102,983 workers , which makes it the most international media corporation in the world. In 2008 the company reported a €16.118 billion consolidated...

 (Germany). A system was delivered to the U.S. Department of Justice to aid the analysis of bootleg recordings.

Editing could be performed at sample accuracy (i.e., 1/50,000 of a second); any mixing was performed digitally.

The sound system in the editing room in the Salt Lake facility used a Threshold SL-10 preamp, a Sumo "The Power" amp, and Infinity

Infinity (audio)

Infinity Systems is an American manufacturer of loudspeakers founded by Arnie Nudell, John Ulrick and Cary Christie in 1968. Since 1983, Infinity has been part of the Harman International Industries group....

 RS4.5 speakers.

Digital Audio Interface

The Digital Audio Interface (DAI) was the input/output path between the Digital Editing System and external hardware. The DAI received raw source data from session tapes and passed the data on to the editing system's computer for storage. Finished (edited) data passed through the DAI from the editing system's computer to a DTR for creation of a master tape. During the editing process, data from the editing system's computer passed through the DAI to a Digital Audio Conversion Unit (DAC Box) in the editing room.

The DAI resided in the Editing System's computer and contained a one-megabyte FIFO. Realtime input/output capacity was eight channels of 16-bit audio data at any of the then standard sample rates.

Digital Delay Unit

To allow for a preview channel during the LP cutting process, Soundstream built a digital delay unit (DDU). Digital data from tape could be delayed by a user selectable time: 3ms to 1.308s in increments of 5.12ms. Delay was accomplished by the use of a variable-depth FIFO or ring buffer.

S-1610 Adapter

So that users of the Sony

Sony

, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....

 PCM-1610 Digital Audio Processor could take advantage of Soundstream's editing system, the company developed the S-1610 Adapter. The adapter was a bidirectional two-channel format converter. Data from the Sony PCM-1610 were converted to the format used by the Soundstream DTR so that the data appearing at the input to the Digital Audio Interface looked to the DAI as if it had come from a DTR. Similarly, finished (edited) data in Soundstream format were restored to the Sony format by the adapter. Sony data were imported/exported at either of the two sample rates 44.1 kHz or 44.1/1.001kHz.

Any metadata in the Sony format were lost in the format conversion. This was a format conversion only, the adapter did not do sample rate conversion.

M Adapter

So that users of the 3M

3M

3M Company , formerly known as the Minnesota Mining and Manufacturing Company, is an American multinational conglomerate corporation based in Maplewood, Minnesota, United States....

Digital Mastering System could take advantage of Soundstream's editing system, the company developed the M Adapter. The adapter was a bidirectional eight-channel format converter. Data from the 3M Digital Mastering System were converted to the format used by the Soundstream DTR so that the data appearing at the input to the Digital Audio Interface looked to the DAI as if it had come from a DTR. Similarly, finished (edited) data in Soundstream format were restored to the 3M format by the adapter.

DAC Box

Essentially derived from the DTR's playback circuitry, the DAC Box was a four channel device used by the Soundstream editors to audition audio data during the editing process. Audio played from the computer through the Digital Audio Interface into the DAC Box.