During World War II, Ampex was a small manufacturer of electric motors and generators. Near the end of the war, while serving in the U.S. Army Signal Corps, Jack Mullin was assigned to investigate German radio and electronics experiments. Mullin acquired two Magnetophon recorders and he brought them to America where he produced modified versions. Bing Crosby, then the biggest star on American radio, disliked doing live broadcasts. In 1946 he had asked the NBC network to allow him to pre-record his shows on acetate discs. When the network refused because of the inferior audio quality of discs, Crosby withdrew from the show for almost a year. In June 1947, Mullin demonstrated his modified tape recorders to Bing Crosby. When Crosby heard a demonstration of Mullin's tape recorders, he immediately saw the potential of the new technology and commissioned Mullin to prepare a test recording of his radio show. After a successful test broadcast, NBC agreed to allow Crosby to pre-record his shows on tape. Crosby immediately appointed Mullin as his chief engineer and invested $50,000 in Ampex (then a small six-man concern) so that the company could develop a commercial production model from Mullin's prototypes.
The company's first tape recorder, the Ampex Model 200, revolutionized the radio and recording industries. In 1948, ABC used an Ampex Model 200 audio recorder for the first-ever U.S. tape delayed radio broadcast of The Bing Crosby Show.
Les Paul, a friend of Crosby's and a regular guest on his shows had already been experimenting with overdubbed recordings on disc. When he received an early Ampex Model 200, he modified the tape recorder by adding additional recording and playback heads, creating the world's first practical tape-based multitrack recording system.
During the early 1950s Ampex began marketing 1 and 2 track machines using 1/4" tape. The line soon expanded into 3 and 4 track models using 1/2" tape. Ampex acquired Orradio Industries in 1959, which became the Ampex Magnetic Tape Division, headquartered in Opelika, Alabama. This made Ampex a manufacturer of both recorders and tape. By the end of that decade Ampex products were much in demand by top recording studios worldwide. In 1959, no longer involved in producing radio shows, Crosby sold his interest in the Ampex Corporation, having played a crucial role in underwriting a technology that changed the broadcasting industry.
Ampex built a handful of machines during the late 1950s that could record as many as 8 tracks on 1" tape, though 4 track machines were widely considered state-of-the-art until about 1967. The demand for more tracks suddenly exploded when musicians heard about the extensive overdubbing done on 4 track machines for Sgt. Pepper's Lonely Hearts Club Band. Recording engineers Geoff Emerick and Ken Townshend working with The Beatles at EMI's Abbey Road Studios also devised a primitive way to link 2 Studer J37 4 track machines together but this did not last long. In 1967 Ampex stepped up production of their 8-track machines with the new MM-1000 to respond to the demand. At the same time 3M Corporation successfully introduced the M56, a competing 8-track machine . Scully Recording Instruments was also briefly successful with a unique 12 track design using 1" tape.
In 1968 Ampex introduced a 16-track version of the MM-1000 which was the world's first 16-track professional tape recorder. It used a 2" tape transport design adapted from the video recording division. It quickly became legendary for its tremendous flexibility, reliability and outstanding sound quality. This brought about the "golden age" of analog multitrack recording, which would last into the early 1990s. Later machines built by Ampex would have as many as 24 tracks. Even more tracks could be made available by linking multiple machines together with SMPTE time code. By the late 1970s Ampex also faced tough competition from Japanese manufacturers. It withdrew from the professional audio tape recorder market entirely in 1983.
By the 1990s, Ampex focused more on video, instrumentation, and data recorders. In 1991, the professional audio recorder line of business was sold to Sprague Magnetics.
The Ampex Recording Media Corporation was spun off in 1995 as Quantegy Inc., and is now known as Quantegy Recording Solutions.
The "Quad" head assembly had 4 heads that rotated at 14,400 rpm. They wrote the video vertically across the width of a tape that was 2 inches (5 cm) wide and ran at 15" (38cm) per second. This allowed hour-long programs to be recorded on one reel of tape. (In 1956, one reel of tape cost $300, equivalent to $2,000 in 2000, and the recorders cost about $75,000 to $100,000, about a half a million dollars today.)
In 1967, Ampex introduced the Ampex VR-3000 portable broadcast video recorder, which revolutionized the recording of high-quality television in the field without the need for long cables and large support vehicles. Broadcast quality images could now be shot anywhere, including from airplanes, helicopters and boats.
The Quadruplex format dominated the broadcast industry for a quarter of a century. The format was licensed to RCA for use in their "television tape recorders." Ampex's invention revolutionized the television industry by eliminating the kinescope process of time-shifting television programs, which required the use of motion picture film. For archival purposes, the kinescope method continued to be used for some years; film was still preferred by archivists. The Ampex broadcast video tape recorder facilitated time-zone broadcast delay so that networks could air programming at the same hour in various time zones. Ampex had trademarked the name "video tape", so competitor RCA called the medium "TV tape" or "television tape". The terms eventually became genericized, and "videotape" is commonly used today.
While the quadruplex recording system per se is no longer in use, the principle evolved into the helical scanning technique used in virtually all video tape machines, such as VHS.
One of the key engineers in the development of the Quadruplex video recorder for Ampex was Ray Dolby, who worked under Charlie Ginsburg and went on to form Dolby Laboratories, a pioneer in audio noise reduction systems.
Playback correction was done with modules from the VR-2000 Quad: Amtec: Horizontal TBC. Colortec: Color TBC in line after the Amtech. Procamp: Processing amplifier on the finial output. New Composite sync insertion, level adjustment.
The DCT and DST formats yield relatively high capacity and speed for data and video. Double-density DST data storage was introduced in 1996. Current products are quad density, introduced in 2000, and a "large" cartridge that holds 660 GB of data.
Ampex Corporation is the parent company of Ampex Data Systems which manufactures digital archiving systems, principally for the broadcast industry. On March 30, 2008, Ampex Corp. filed for Chapter 11 reorganization, according to its web site. It continues normal operations and plans to re-emerge.

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