Soundstream Inc. was the first United States

audiophile An audiophile is a person who is enthusiastic about high-fidelity sound reproduction. An audiophile seeks to reproduce the sound of a piece of recorded music or a live musical performance, typically inside closed headphones, In-ear monitors, open ...

digital audio Digital audio is a representation of sound recorded in, or converted into, digital form. In digital audio, the sound wave of the audio signal is typically encoded as numerical samples in a continuous sequence. For example, in CD audio, samp ...

recording company, providing commercial services for recording and computer-based editing.Robert Easton, ''Soundstream, the first Digital Studio'', Recording Engineer/Producer, April 1976

Company

Soundstream was founded in 1975 in

Salt Lake City Salt Lake City (often shortened to Salt Lake and abbreviated as SLC) is the capital and most populous city of Utah, United States. It is the seat of Salt Lake County, the most populous county in Utah. With a population of 200,133 in 2020, th ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

by Dr. Thomas G. Stockham, Jr. The company provided worldwide on-location recording services to

Telarc Telarc International Corporation is an American audiophile independent record label founded in 1977 by two classically trained musicians and former teachers, Jack Renner (recording engineer), Jack Renner and Robert Woods (producer), Robert Woods. ...

Delos The island of Delos (; el, Δήλος ; Attic: , Doric: ), near Mykonos, near the centre of the Cyclades archipelago, is one of the most important mythological, historical, and archaeological sites in Greece. The excavations in the island ar ...

RCA The RCA Corporation was a major American electronics company, which was founded as the Radio Corporation of America in 1919. It was initially a patent trust owned by General Electric (GE), Westinghouse, AT&T Corporation and United Fruit Comp ...

Philips Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters is ...

Vanguard The vanguard (also called the advance guard) is the leading part of an advancing military formation. It has a number of functions, including seeking out the enemy and securing ground in advance of the main force. History The vanguard derives f ...

Varèse Sarabande Varèse Sarabande is an American record label, owned by Concord Music Group and 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 r ...

Angel In various theistic religious traditions an angel is a supernatural spiritual being who serves God. Abrahamic religions often depict angels as benevolent celestial intermediaries between God (or Heaven) and humanity. Other roles ...

Warner Brothers Warner Bros. Entertainment Inc. (commonly known as Warner Bros. or abbreviated as WB) is an American film and entertainment studio headquartered at the Warner Bros. Studios complex in Burbank, California, and a subsidiary of Warner Bros. D ...

CBS CBS Broadcasting Inc., commonly shortened to CBS, the abbreviation of its former legal name Columbia Broadcasting System, is an American commercial broadcast television and radio network serving as the flagship property of the CBS Entertainm ...

Decca Decca may refer to: Music * Decca Records or Decca Music Group, a record label * Decca Gold, a classical music record label owned by Universal Music Group * Decca Broadway, a musical theater record label * Decca Studios, a recording facility in We ...

, Chalfont, and other labels. They manufactured a total of 18 digital recorders, of which seven were sold and the rest leased out. Although most recordings were of

classical music Classical music generally refers to the art music of the Western world, considered to be distinct from Western folk music or popular music traditions. It is sometimes distinguished as Western classical music, as the term "classical music" al ...

, the range included

country A country is a distinct part of the world, such as a state, nation, or other political entity. It may be a sovereign state or make up one part of a larger state. For example, the country of Japan is an independent, sovereign state, whi ...

, rock,

jazz Jazz is a music genre that originated in the African-American communities of New Orleans, Louisiana in the late 19th and early 20th centuries, with its roots in blues and ragtime. Since the 1920s Jazz Age, it has been recognized as a m ...

pop Pop or POP may refer to: Arts, entertainment, and media Music * Pop music, a musical genre Artists * POP, a Japanese idol group now known as Gang Parade * Pop!, a UK pop group * Pop! featuring Angie Hart, an Australian band Albums * ''Pop'' ( ...

, and

avant-garde The avant-garde (; In 'advance guard' or ' vanguard', literally 'fore-guard') is a person or work that is experimental, radical, or unorthodox with respect to art, culture, or society.John Picchione, The New Avant-garde in Italy: Theoretica ...

. The first US live

digital recording In digital recording, an audio or video signal is converted into a stream of discrete numbers representing the changes over time in air pressure for audio, or chroma and luminance values for video. This number stream is saved to a storage ...

was made in 1976 by Soundstream's prototype 37 kHz, 16-bit, two channel recorder.

New World Records New World Records is a record label that was established in 1975 through a Rockefeller Foundation grant to celebrate America's bicentennial (1976) by producing a 100-LP anthology, with American music from many genres.Santa Fe Opera's performance of Virgil Thomson's ''

The Mother of Us All ''The Mother of Us All'' is a two-act opera composed by Virgil Thomson to a libretto by Gertrude Stein. Thomson and Stein met in 1945 to begin the writing process, almost twenty years after their first collaborative project, the opera ''Four Sain ...

'', and provided Soundstream with a stereo feed from their multitrack console. Soundstream demonstrated this recording at the Fall 1976

AES Convention The Audio Engineering Society (AES) is a professional body for engineers, scientists, other individuals with an interest or involvement in the professional audio industry. The membership largely comprises engineers developing devices or products ...

; however the resulting record was pressed not from the digital master but from the analog tape that New World recorded themselves concurrently.Thomas Fine, ''The Dawn of Commercial Digital Recording'', ARSC Journal Volume 39, No. 1, Spring 2008 Critiques of the recording, most notably from Telarc's Jack Renner and Robert Woods, led directly to the improved four-channel, 50 kHz sample rate recorder that was used for all of Soundstream's future commercial releases. Also in 1976, Soundstream restored acoustic (pre-electronic) recordings of

Enrico Caruso Enrico Caruso (, , ; 25 February 1873 – 2 August 1921) was an Italian operatic first lyrical tenor then dramatic tenor. He sang to great acclaim at the major opera houses of Europe and the Americas, appearing in a wide variety of roles (74) ...

, by digitizing the recordings on a computer, and processing them using a technique called "blind

deconvolution In mathematics, deconvolution is the operation inverse to convolution. Both operations are used in signal processing and image processing. For example, it may be possible to recover the original signal after a filter (convolution) by using a deco ...

".Thomas Stockham, ''Restoration of Old Acoustic Recordings by means of Digital Signal Processing'', 41st Convention of the Audio Engineering Society, 1971a These were released by

RCA Records RCA Records is an American record label currently owned by Sony Music Entertainment, a subsidiary of Sony Corporation of America. It is one of Sony Music's four flagship labels, alongside RCA's former long-time rival Columbia Records; also ...

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. Soundstream's first commercially released recording, ''Diahann Carroll With the Duke Ellington Orchestra Under The Direction Of Mercer Ellington – A Tribute To Ethel Waters'' (on the Orinda label) appeared in January 1978. Over the next three years, almost 50% of all classical music recorded digitally used Soundstream equipment, over 200 recordings in all. The Canadian rock band, True Myth, recorded their self-titled debut album using the Soundstream unit, the first Canadian digital recording. The band recorded the album live to two-track stereo in Jack Richardson's studio, Nimbus Nine, located in Toronto, Canada. Unlike its competitors, Soundstream's analog circuitry was transformerless, permitting a frequency response to 0 Hz ( DC). This accounted for the "bass drum heard round the world"IEEE Global History Network
Telarc, Frederick Fennell, and an Overture to Digital Recording
Interview: Jack Renner of Telarc: Direct from Cleveland!; Stereophile October 1998 review of the 1978 Telarc recording of ''Frederick Fennell: The Cleveland Symphonic Winds''.Tracy Eddy, ''The Bass Drum Heard 'Round the World: Telarc, Frederick Fennell, and an Overture to Digital Recording''
IEEE Today's Engineer Online, July 2005
/ref>World Book Encyclopedia, ''Yearbook'', 1978 Soundstream collaborated with Telarc for several years, producing legendary symphonic recordings; the earliest ones are chronicled in Renner.Jack Renner, ''The Roots of Telarc'', Telarc newsletter, Fall 1992 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 Super Audio CD (SACD) is an optical disc format for audio storage introduced in 1999. It was developed jointly by Sony and Philips Electronics and intended to be the successor to the Compact Disc (CD) format. The SACD format allows multiple au ...

format. Soundstream recordings made before the advent of the CD were released as high-quality vinyl LP albums. Despite analog playback, many of these releases were sufficiently impressive to gain an early acceptance for digital audio.David Ranada, ''A Dozen Digital Demo Discs'', Stereo Review, January 1980BM/E, ''New Audio Tape Machine Delivers 'Digital Fidelity'', February 1977 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.Thomas Stockham, ''A-D and D-A Converters: their Effect on Digital Audio Fidelity'', 41st Convention of the Audio Engineering Society, 1971bThomas Stockham, ''Records of the Future'', Journal of the Audio Engineering Society, October 1977 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.John Miklosz, ''Digital Audio System uses Rectangular Records'', Electronic Engineering Times, November 23, 1981 This effort was eclipsed by the rise of the CD, leading to the company's demise in 1985.

Technology

The company developed its four-channel, 16 bit, 50 ksps recorder in 1977. The Soundstream Digital Tape Recorder (DTR) consisted of a modified

Honeywell Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building technologies, performance ma ...

5600E instrumentation

transport Transport (in British English), or transportation (in American English), is the intentional movement of humans, animals, and goods from one location to another. Modes of transport include air, land ( rail and road), water, cable, pipelin ...

and

analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...

and

digital Digital usually refers to something using discrete digits, often binary digits. Technology and computing Hardware *Digital electronics, electronic circuits which operate using digital signals ** Digital camera, which captures and stores digital ...

circuitry designed and built by Soundstream. There were 2 series of DTR's built. the first series (SN 1–4) was produced from ~1977 to 1979 and the second series (SN 5- 13) produced ~1980 to 1981. While being tape format compatible and looking nearly identical from the outside, the later series are easily identified by the second set of tape transport control buttons. Many Internal cards are not 100% compatible between the 2 series.

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 antialias filter (custom made by TTE Filters) is a passive 11 pole elliptical function filter with a -3 dB point of 22.5 kHz. The analog signal path from input XLR connector to the A/D converter is DC coupled. The filtered analog signal passed through a custom

sample and hold In electronics, a sample and hold (also known as sample and follow) circuit is an analog device that samples (captures, takes) the voltage of a continuously varying analog signal and holds (locks, freezes) its value at a constant level for a ...

and was digitized by an Analogic MP8016 16-bit Analog-to-Digital Converter operating at a 50 kHz sample rate. A three-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. The two tracks are laterally separated by ~ 11mm on the 1" tape thus avoiding the same tape dropout from affecting both tracks containing identical channel information. Encoding of the 16 bit audio at the time of recording inverts every other audio bit in order to minimize DC going to tape (magnetic channel) in quiet passages when the MSB's were mostly zeros. Another effect of the encoding process was to increase AC in the channel code to aid in clock recovery (bit sync) on playback. The every other bit inversion encoding process is reversed on playback so there is no effect on audio quality. 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. The first stage of data recovery was the data slicer which automatically detected and adjusted to the ideal threshold for detecting the zero crossings of the magnetic channel data. This reduced clock recovery jitter. Because the data recorded on tape are necessarily bandwidth-limited, the data slicer squared-up the data signals into binary logic level signals and then recovered 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 (DAC) at the original crystal-controlled sample rate. The DAC analog output signal was buffered by an Analogic MP201A distortion suppression amplifier (aka deglitching amplifier). The MP201A suppresses the glitches present during the narrow segment of time that the binary input word to the DAC was transitioning from one sample to another. The analog signal from the distortion suppression amplifier was routed to the output low-pass (reconstruction) filter that is identical to the input anti-alias filter and then to NE5534 based output buffer amplifier with a discrete transistor output stage. Voltage and current gain sufficient for +20 dBm into 150 ohms was provided by the output-buffer amplifier with the signal then output at the XLR connector on the DTR's rear panel. The output signal path from DAC to output XLR connector was DC coupled.

Honeywell Tape Drives

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

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 is an American electronics company founded in 1944 by Alexander M. Poniatoff as a spin-off of Dalmo-Victor. The name AMPEX is a portmanteau, created by its founder, which stands for Alexander M. Poniatoff Excellence.AbramsoThe History ...

460

reel-to-reel Reel-to-reel audio tape recording, also called open-reel recording, is magnetic tape audio recording in which the recording tape is spooled between reels. To prepare for use, the ''supply reel'' (or ''feed reel'') containing the tape is pla ...

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

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 (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until ...

PDP 11/60 computer running the DAP (''Digital Audio Processor'') editing software (written by Soundstream employee Robert Ingebretsen), 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, a text-based

video display terminal A computer terminal is an electronic or electromechanical hardware device that can be used for entering data into, and transcribing data from, a computer or a computing system. The teletype was an example of an early-day hard-copy terminal a ...

for entering commands to operate and control the DAP software, and a

storage oscilloscope An oscilloscope (informally a scope) is a type of electronic test instrument that graphically displays varying electrical voltages as a two-dimensional plot of one or more signals as a function of time. The main purposes are to display repetitiv ...

to display the waveforms of the audio being edited or processed. For all intents and purposes, this system was the very first

digital audio workstation A digital audio workstation (DAW) is an electronic device or application software used for recording, editing and producing audio files. DAWs come in a wide variety of configurations from a single software program on a laptop, to an integr ...

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

Paramount Pictures Paramount Pictures Corporation is an American film and television production company, production and Distribution (marketing), distribution company and the main namesake division of Paramount Global (formerly ViacomCBS). It is the fifth-oldes ...

(Hollywood), RCA (New York), and

Bertelsmann Bertelsmann SE & Co. KGaA () is a German private multinational conglomerate corporation based in Gütersloh, North Rhine-Westphalia, Germany. It is one of the world's largest media conglomerates, and is also active in the service sector and ...

(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 is that which is boundless, endless, or larger than any natural number. It is often denoted by the infinity symbol . Since the time of the ancient Greeks, the philosophical nature of infinity was the subject of many discussions am ...

RS4.5 speakers.

Ancillary equipment

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 , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

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 In digital audio, 44,100 Hz (alternately represented as 44.1 kHz) is a common sampling frequency. Analog audio is often recorded by sampling it 44,100 times per second, and then these samples are used to reconstruct the audio signal w ...

or 44.1/1.001 kHz. 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 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.

References

{{Authority control Digital audio Audio storage 1975 establishments in Utah