Alan Dower Blumlein (29 June 1903 – 7 June 1942) was an English

electronics The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...

engineer, notable for his many inventions in telecommunications,

sound recording Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recording te ...

stereophonic sound Stereophonic sound, or more commonly stereo, is a method of sound reproduction that recreates a multi-directional, 3-dimensional audible perspective. This is usually achieved by using two independent audio channels through a configuration ...

, television and radar. He received 128 patents and was considered one of the most significant engineers and inventors of his time. He died during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

on 7 June 1942, aged 38, during the secret trial of an H2S airborne radar system then under development, when all on board the

Halifax bomber The Handley Page Halifax is a British Royal Air Force (RAF) four-engined heavy bomber of the World War II, Second World War. It was developed by Handley Page to the same specification as the contemporary twin-engine Avro Manchester. The Halifa ...

in which he was flying were killed when it

crashed "Crashed" is the third U.S. rock Single (music), single, (the fifth overall), from the band Daughtry (band), Daughtry's debut album. It was released only to U.S. rock stations on September 5, 2007. Upon its release the song got adds at those stat ...

Welsh Bicknor Welsh Bicknor ( cy, Llangystennin Garth Brenni) is an area in the far south of the English county of Herefordshire. Despite its name, it is not now in Wales, but it was historically a detached parish (exclave) of the county of Monmouthshire. It ...

in Herefordshire.

Early life

Alan Dower Blumlein was born on 29 June 1903 in

Hampstead Hampstead () is an area in London, which lies northwest of Charing Cross, and extends from Watling Street, the A5 road (Roman Watling Street) to Hampstead Heath, a large, hilly expanse of parkland. The area forms the northwest part of the Lon ...

, London. His father, Semmy Blumlein, was a German-born naturalised British subject. Semmy was the son of Joseph Blumlein, a German of

Jewish Jews ( he, יְהוּדִים, , ) or Jewish people are an ethnoreligious group and nation originating from the Israelites Israelite origins and kingdom: "The first act in the long drama of Jewish history is the age of the Israelites""The ...

descent, and Philippine Hellmann, a French woman of German descent.Semmy Blumlein's father, Joseph B. Blumlein was Jewish, ''see Burns, p. 2'' Alan's mother, Jessie Dower, was Scottish, daughter of William Dower (born 1837) who went to South Africa for the

London Missionary Society The London Missionary Society was an interdenominational evangelical missionary society formed in England in 1795 at the instigation of Welsh Congregationalist minister Edward Williams. It was largely Reformed in outlook, with Congregational miss ...

. Alan was christened as a

Presbyterian Presbyterianism is a part of the Reformed tradition within Protestantism that broke from the Roman Catholic Church in Scotland by John Knox, who was a priest at St. Giles Cathedral (Church of Scotland). Presbyterian churches derive their nam ...

; he later married in a

Church of England The Church of England (C of E) is the established Christian church in England and the mother church of the international Anglican Communion. It traces its history to the Christian church recorded as existing in the Roman province of Britain ...

parish church. Alan Blumlein's future career seemed to have been determined by the age of seven, when he presented his father with an invoice for repairing the doorbell, signed "Alan Blumlein, Electrical Engineer" (with "paid" scrawled in pencil). His sister claimed that he could not read proficiently until he was 12. He replied "no, but I knew a lot of quadratic equations!" After leaving Highgate School in 1921, he studied at

City and Guilds College The Faculty of Engineering is the engineering school of Imperial College London, and one of the three main faculties the college. It was formed in 2001 from the former City and Guilds College and the Royal School of Mines—two of the three o ...

(part of

Imperial College Imperial College London (legally Imperial College of Science, Technology and Medicine) is a public research university in London, United Kingdom. Its history began with Prince Albert, consort of Queen Victoria, who developed his vision for a cu ...

). He won a Governors' scholarship and joined the second year of the course. He graduated with a

First-Class Honours The British undergraduate degree classification system is a grading structure for undergraduate degrees or bachelor's degrees and integrated master's degrees in the United Kingdom. The system has been applied (sometimes with significant variati ...

BSc A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University ...

two years later. In mid-1930, Blumlein met Doreen Lane, a preparatory school teacher five years his junior. After two-and-a-half years of courtship the two were married in 1933. Lane was warned by acquaintances before the wedding that, "There was a joke amongst some of his friends, they used to call it 'Blumlein-itis' or 'First Class Mind'. It seems that he didn't want to know anyone who didn't have a first class mind." Recording engineer Joseph B. Kaye, known as J. B. Kaye, who was Blumlein's closest friend and best man at the wedding, thought the couple were well matched.

Career and inventions

Telecommunications

In 1924 Blumlein started his first job at

International Western Electric Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mul ...

, a division of the

Western Electric Company The Western Electric Company was an American electrical engineering and manufacturing company officially founded in 1869. A wholly owned subsidiary of American Telephone & Telegraph for most of its lifespan, it served as the primary equipment m ...

. The company subsequently became International Standard Electric Corporation and then, later on,

Standard Telephones and Cables Standard Telephones and Cables Ltd (later STC plc) was a British manufacturer of telephone, telegraph, radio, telecommunications, and related equipment. During its history, STC invented and developed several groundbreaking new technologies incl ...

(STC). During his time there, he measured the

amplitude The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value. There are various definitions of amplit ...

frequency response In signal processing and electronics, the frequency response of a system is the quantitative measure of the magnitude and phase of the output as a function of input frequency. The frequency response is widely used in the design and analysis of sy ...

of human ears, and used the results to design the first

weighting The process of weighting involves emphasizing the contribution of particular aspects of a phenomenon (or of a set of data) over others to an outcome or result; thereby highlighting those aspects in comparison to others in the analysis. That i ...

networks. In 1924 he published (with Professor Edward Mallett) the first of his only two IEE papers, on high-frequency resistance measurement. This won him the IEE's Premium award for innovation. The following year he wrote (with Norman Kipping) a series of seven articles for

Wireless World ''Electronics World'' (''Wireless World'', founded in 1913, and in September 1984 renamed ''Electronics & Wireless World'') is a technical magazine in electronics and RF engineering aimed at professional design engineers. It is produced monthly in ...

. In 1925 and 1926, Blumlein and John Percy Johns designed an improved form of loading coil which reduced loss and

crosstalk In electronics, crosstalk is any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, induc ...

in long-distance telephone lines. These were used until the end of the analogue telephony era. The same duo also invented an improved form of AC measurement

bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...

which became known as the '' Blumlein Bridge'' and subsequently the ''

transformer ratio arm bridge The transformer ratio arm bridge or TRA bridge is a type of bridge circuit used for measuring electronic components, using a.c. It can be designed to work in terms of either impedance or admittance. It can be used on resistors, capacitors and ind ...

''. These two inventions were the basis for Blumlein's first two patents. His inventions while working at STC resulted in another five patents, which were not awarded until after he left the company in 1929.

Sound recording

In 1929 Blumlein resigned from STC and joined the

Columbia Graphophone Company Columbia Graphophone Co. Ltd. was one of the earliest phonograph, gramophone companies in the United Kingdom. Founded in 1917 as an offshoot of the American Columbia Records, Columbia Phonograph Company, it became an independent British-owned ...

, where he reported directly to general manager

Isaac Shoenberg Sir Isaac Shoenberg (1 March 1880 – 25 January 1963) was a British electronic engineer born in Belarus who was best known for his role in the history of television. He was the head of the EMI research team that developed the 405-line (Marconi-EM ...

. His first project was to find a method of disc cutting that circumvented a Bell patent in the ''Western Electric moving-iron cutting head'' then used, and on which substantial royalties had to be paid. He invented the moving-coil disc cutting head, which not only got around the patent but offered greatly improved sound quality. He led a small team which developed the concept into a practical cutter. The other principal team members were Herbert Holman and Henry "Ham" Clark. Their work resulted in several patents. Early in 1931, the Columbia Graphophone Company and the

Gramophone Company The Gramophone Company Limited (The Gramophone Co. Ltd.), based in the United Kingdom and founded by Emil Berliner, was one of the early recording companies, the parent organisation for the ''His Master's Voice (HMV)'' label, and the European ...

merged and became

EMI EMI Group Limited (originally an initialism for Electric and Musical Industries, also referred to as EMI Records Ltd. or simply EMI) was a British Transnational corporation, transnational Conglomerate (company), conglomerate founded in March 1 ...

. New joint research laboratories were set up at Hayes and Blumlein was officially transferred there on 1 November the same year. During the early 1930s Blumlein and Herbert Holman developed a series of moving-coil microphones, which were used in EMI recording studios and by the

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