Please answer the following question: Information: - In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure and displacement, through a transmission medium such as air or water. In physiology and psychology, sound is the "reception" of such waves and their "perception" by the brain. Humans can hear sound waves with frequencies between about 20Hz and 20kHz. Sound above 20kHz is ultrasound and below 20Hz is infrasound. Other animals have different hearing ranges. - Audio equipment refers to devices that reproduce, record, or process sound. This includes microphones, radio receivers, AV receivers, CD players, tape recorders, amplifiers, mixing consoles, effects units, and loudspeakers. - A loudspeaker (or loud-speaker or speaker) is an electroacoustic transducer; which converts an electrical audio signal into a corresponding sound. The most widely used type of speaker in the 2010s is the dynamic speaker, invented in 1925 by Edward W. Kellogg and Chester W. Rice. The dynamic speaker operates on the same basic principle as a dynamic microphone, but in reverse, to produce sound from an electrical signal. When an alternating current electrical audio signal is applied to its voice coil, a coil of wire suspended in a circular gap between the poles of a permanent magnet, the coil is forced to move rapidly back and forth due to Faraday's law of induction, which causes a diaphragm (usually conically shaped) attached to the coil to move back and forth, pushing on the air to create sound waves. Besides this most common method, there are several alternative technologies that can be used to convert an electrical signal into sound. The sound source (e.g., a sound recording or a microphone) must be amplified or strengthened with an audio power amplifier before the signal is sent to the speaker. - ReVox is a brand name of Swiss audio equipment registered by Studer on March 27 , 1951 . The first Studer - designed tape recorders were branded Dynavox . After the first production series of Dynavox recorders , a new marketing company was formed in 1950 called ELA AG. Revox was adopted as the brand name for amateur recorders , while the professional machines retained the Studer name . The first Revox - branded tape recorder was the T26 , in 1952 , successor to the Dynavox 100 . The T26 was also made available as a radio - recorder combination unit . 2500 T26 recorders were made , priced at 1395.00 Swiss francs . The A36 , the first 36 series recorder . became available in 1954 . Unusual features for the time were pushbutton solenoid transport operations and a direct - drive capstan with no belts or idler wheels . The B36 of 1956 was the first 3 - head model , the D36 of 1960 was the first stereo model . The company moved to Loffingen , West Germany , in 1966 , due to labour issues in Switzerland . But the building of a second factory was started in Regensdorf , Switzerland in 1967 - to open in 1968 . In 1967 the 36 - series tape recorders ended with the G36 , and were superseded by the transistorised A77 with a servo - controlled direct drive capstan . Over 80,000 36 - series recorders had been manufactured . The A77 was complemented by an integrated amplifier ( A78 ) and FM tuner ( A76 ) . In 1990 Willi Studer sold the Studer Revox Group to Motor - Columbus AG , including all subsidiary companies . In 1991 , Motor - Columbus split the Studer Revox Group into Studer ( Pro ) , Revox ( HiFi ) and a Manufacturing - division . Motor - Columbus sold several subsidiaries and plants . The extensive reorganization culminated in the sale of the Studer Group to Harman International Inc. , in March 1994 . The Revox Group was excluded and sold to private investors . On March 17 , 1994 , Harman International Industries completed its acquisition and acquired from Motor - Columbus AG 100 % of Studer Revox AG. Harman paid... - Studer is a designer and manufacturer of advanced audio equipment for recording studios and broadcasters. The company was founded in Zurich, Switzerland in 1948 by Dr. Willi Studer. It initially became famous in the 1950s for its professional tape recorders. In the 1990s the company moved into the mixing console business. - A CD player is an electronic device that plays audio compact discs, which are a digital optical disc data storage format. CD players were first sold to consumers in 1982. CDs typically contain recordings of audio material such as music. CD players are often a part of home stereo systems, car audio systems, and personal computers. With the exception of CD boomboxes, most CD players do not produce sound by themselves. Most CD players only produce an output signal via a headphone jack and/or RCA jacks. To listen to music using a CD player with a headphone output jack, the user plugs headphones or earphones into the headphone jack. To use a CD player in a home stereo system, the user connects an RCA cable to the RCA jacks or other outputs and connects it to a hi-fi (or other amplifier) and loudspeakers for listening to music. They are also manufactured as portable devices, which are battery powered and typically used with headphones. Given the information, choose the subject and object entities that have the relation of 'inception'.
A:
revox , 1948