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A hard disk recorder (HDR) is a system that uses a high-capacity hard disk to record digital audio or digital video. Hard disk recording systems represent an alternative to reel-to-reel audio tape recording and video tape recorders, and provide non-linear editing capabilities unavailable using tape recorders. Audio HDR systems, which can be standalone or computer-based, are typically combined with provisions for digital mixing and processing of the audio signal to produce a digital audio workstation (DAW).
Direct-to-disk recording (DDR) refers to methods which may also use optical disc recording technologies such as DVD, and Compact disc.
Prior to the 1980s, most recording studios used analog multitrack recorders, typically based on reel-to-reel tape. The first commercial hard disk recording system was the Sample-to-Disk 16-bit, 50 kHz digital recording option for the New England Digital Synclavier II in 1982. Stereo audio was not immediately available due to data input and output limitations on hard drives of that time. [1] The high cost and limited capacity of these solutions limited their use to large professional audio recording studios, and even then, they were usually reserved for specific applications such as film post-production.
With the arrival of the compact disc in 1982, digital recording became a major area of development by equipment makers. Several affordable solutions were released during the late 1980s and early 90s; many of these continued to use tape, either in reels, or in more manageable videocassettes. In 1993, iZ Technology Corporation developed RADAR (Random Access Digital Audio Recorder distributed by Otari), designed to replace 24-track tape machines. By the mid-1990s, with the steady decline of hard disk prices and the corresponding increases in capacity and portability, the cost of hard disk recording systems had dropped to the point where they became affordable for even smaller studios. Hard disk systems have since become the preferred method for studio recording.
On January 14, 2004, Engineers from Fairlight, WaveFrame and AMS were awarded Academy Scientific and Technical Awards for the development of hard disk recording technology [2]
One major advantage of recording audio to a hard disk is that it allows for non-linear editing. Audio data can be accessed randomly and therefore can be edited non-destructively, that is, the original material is not changed in any way. Non-linear editing is not inherent to every hard-disk recording system, however. Different manufacturers implement different degrees of this facility.
Hard disk recorders are often combined with a digital mixing console and are an integral part of a digital audio workstation (DAW). In this form, complex tasks can be automated, freeing the audio engineer from performing a final mix in real time.
A personal computer can be used as a hard disk recorder with appropriate software; nowadays this solution is often preferred, as it provides a more flexible interface to the studio engineer. Many studio-grade systems provide external hardware, particularly for the analog-to-digital conversion stages, while less expensive software systems can use the sound card included with any modern computer.
The major constraints on any hard disk recording system are the storage capacity, transfer rate, and processor speed. Some systems use lossy audio compression to minimize the first two factors. This solution is becoming increasingly rare, thanks to rapid increases in hard disk capacity.
Stand-alone hard disk recorders are able to record audio or video without requiring a computer. Examples of notable stand-alone hard disk recorders and manufacturers include Alesis, Akai, Fostex, Korg, Mackie, TASCAM, Roland Corporation, Yamaha Pro Audio, RADAR and Zoom HD8 and HD16.
Miniaturization of recording and storage technology for consumer video already allows the non-professional user to directly record home movies to a permanent storage medium like DVD. [3]
DDRs have replaced Magnetic tape based DV, Digital8, 8mm Video Format, VHS and MicroMV video tape recorders.
Professional television studio DDRs video servers are being used to replace video tape recorders (VTR)s and VTR Cart machines, that playout television commercials and TV shows. DAWs are used in professional audio recording studios. Computer software can implement a hard disk recorder function.
Consumer applications include camcorders to high-end tapeless camcorders, digital video recorder (DVR) and set top box models like TiVo and personal computer based recorders. More professional applications include non-linear editing (NLE) systems like Avid Technology video editing systems, recording television productions/filmmaking in the field with professional video cameras in digital cinematography for digital cinema productions. Hard disk recorders are used in professional television studio from small systems able to record 2 hours to large multi port playout systems supporting hundreds of hours of material.
Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic tape can with relative ease record and play back audio, visual, and binary computer data.
The VHS is a standard for consumer-level analog video recording on tape cassettes, introduced in 1976 by the Victor Company of Japan (JVC). It was the dominant home video format throughout the tape media period in the late 1970s, 1980s, and 1990s.
DV is a family of codecs and tape formats used for storing digital video, launched in 1995 by a consortium of video camera manufacturers led by Sony and Panasonic. It includes the recording or cassette formats DV, MiniDV, DVCAM, Digital8, HDV, DVCPro, DVCPro50 and DVCProHD. DV has been used primarily for video recording with camcorders in the amateur and professional sectors.
Digital Audio Tape is a signal recording and playback medium developed by Sony and introduced in 1987. In appearance it is similar to a Compact Cassette, using 3.81 mm / 0.15" magnetic tape enclosed in a protective shell, but is roughly half the size at 73 mm × 54 mm × 10.5 mm. The recording is digital rather than analog. DAT can record at sampling rates equal to, as well as higher and lower than a CD at 16 bits quantization. If a comparable digital source is copied without returning to the analogue domain, then the DAT will produce an exact clone, unlike other digital media such as Digital Compact Cassette or non-Hi-MD MiniDisc, both of which use a lossy data-reduction system.
Non-linear editing is a form of offline editing for audio, video, and image editing. In offline editing, the original content is not modified in the course of editing. In non-linear editing, edits are specified and modified by specialized software. A pointer-based playlist, effectively an edit decision list (EDL), for video and audio, or a directed acyclic graph for still images, is used to keep track of edits. Each time the edited audio, video, or image is rendered, played back, or accessed, it is reconstructed from the original source and the specified editing steps. Although this process is more computationally intensive than directly modifying the original content, changing the edits themselves can be almost instantaneous, and it prevents further generation loss as the audio, video, or image is edited.
Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes have also been used for storing scientific or medical data, such as the data produced by an electrocardiogram.
Ampex Data Systems Corporation is an American electronics company founded in 1944 by Alexander M. Poniatoff as a spin-off of Dalmo-Victor. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence. Ampex operates as Ampex Data Systems Corporation, a subsidiary of Delta Information Systems, and consists of two business units. The Silicon Valley unit, known internally as Ampex Data Systems (ADS), manufactures digital data storage systems capable of functioning in harsh environments. The Colorado Springs, Colorado, unit, referred to as Ampex Intelligent Systems (AIS), serves as a laboratory and hub for the company's line of industrial control systems, cyber security products and services and its artificial intelligence/machine learning technology.
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 containing the tape is placed on a spindle or hub. The end of the tape is manually pulled from the reel, threaded through mechanical guides and over a tape head assembly, and attached by friction to the hub of the second, initially empty takeup reel. Reel-to-reel systems use tape that is 1⁄4, 1⁄2, 1, or 2 inches wide, which normally moves at 3+3⁄4, 7+1⁄2, 15 or 30 inches per second. Domestic consumer machines almost always used 1⁄4 inch (6.35 mm) or narrower tape and many offered slower speeds such as 1+7⁄8 inches per second (4.762 cm/s). All standard tape speeds are derived as a binary submultiple of 30 inches per second.
Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, Betacam singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself.
A digital audio workstation 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 integrated stand-alone unit, all the way to a highly complex configuration of numerous components controlled by a central computer. Regardless of configuration, modern DAWs have a central interface that allows the user to alter and mix multiple recordings and tracks into a final produced piece.
Broadcast automation incorporates the use of broadcast programming technology to automate broadcasting operations. Used either at a broadcast network, radio station or a television station, it can run a facility in the absence of a human operator. They can also run in a live assist mode when there are on-air personnel present at the master control, television studio or control room.
1-inch Type C Helical Scan or SMPTE C is a professional reel-to-reel analog recording helical scan videotape format co-developed and introduced by Ampex and Sony in 1976. It became the replacement in the professional video and broadcast television industries for the then-incumbent 2-inch quadruplex videotape open-reel format. Additionally, it replaced the unsuccessful type A format, also developed by Ampex, and primarily in mainland Europe, it supplemented the type B format, developed by the Fernseh division of Bosch.
1-inch Type B Helical Scan or SMPTE B is a reel-to-reel analog recording video tape format developed by the Bosch Fernseh division of Bosch in Germany in 1976. The magnetic tape format became the broadcasting standard in continental Europe, but adoption was limited in the United States and United Kingdom, where the Type C videotape format met with greater success.
Offline editing is the creative storytelling stage of film making and television production where the structure, mood, pacing and story of the final show are defined. Many versions and revisions are presented and considered at this stage until the edit gets to a stage known as picture lock. This is when the process then moves on to the next stages of post production known as online editing, colour grading and audio mixing.
Digital audio cassette formats introduced to the professional audio and consumer markets:
In broadcasting, channel playout is the generation of the source signal of a radio or television channel produced by a broadcaster, coupled with the transmission of this signal for primary distribution or direct-to-audience distribution via any network. Such radio or television distribution networks include terrestrial broadcasting, cable networks, satellites, Internet Protocol television, OTT Video, point-to-point transport over managed networks or the public Internet, etc.
The history of sound recording - which has progressed in waves, driven by the invention and commercial introduction of new technologies — can be roughly divided into four main periods:
The Sony 9-Pin Protocol or P1 protocol is a two-way communications protocol to control advanced video recorders. Sony introduced this protocol to control reel-to-reel type C video tape recorders (VTR) as well as videocassette recorders (VCR). It uses an DE-9 D-Sub connector with 9 pins, where bi-directional communication takes place over a four wire cable according to the RS-422 standard.
A color suite is the control room for color grading video in a post-production environment.
In the field of professional broadcasting, an end-to-end workflow is called tapeless when part, or all of it, is made without any use of audio tape recorders or videotape machines; video and audio sources being ingested, recorded, edited and played out entirely on digital video systems.