Task: Question Answering
Input (English): Context: Lahr is a city in western Baden-Württemberg, Germany, approximately 50 km north of Freiburg in Breisgau, 40 km south east of Strasbourg, and 95 km south west of Karlsruhe. It is the second largest city in Ortenau (district) after Offenburg, and serves as an intermediate economic centre for the cities and towns of Ettenheim, Friesenheim, Kappel-Grafenhausen, Kippenheim, Mahlberg, Meißenheim, Ringsheim, Rust, Schuttertal, Schwanau and Seelbach., The phonograph is a device invented in 1877 for the mechanical recording and reproduction of sound. In its later forms it is also called a gramophone (as a trademark since 1887, as a generic name since c. 1900). The sound vibration waveforms are recorded as corresponding physical deviations of a spiral groove engraved, etched, incised, or impressed into the surface of a rotating cylinder or disc, called a "record". To recreate the sound, the surface is similarly rotated while a playback stylus traces the groove and is therefore vibrated by it, very faintly reproducing the recorded sound. In early acoustic phonographs, the stylus vibrated a diaphragm which produced sound waves which were coupled to the open air through a flaring horn, or directly to the listener's ears through stethoscope-type earphones. In later electric phonographs (also known as record players (since 1940s) or, most recently, turntables), the motions of the stylus are converted into an analogous electrical signal by a transducer, then converted back into sound by a loudspeaker., The City Municipality of Bremen is a Hanseatic city in northwestern Germany, which belongs to the state Free Hanseatic City of Bremen (also called just "Bremen" for short)., Established in 1948, the Audio Engineering Society (AES) draws its membership from engineers, scientists, other individuals with an interest or involvement in the professional audio industry. The membership largely comprises engineers developing devices or products for audio, and persons working in audio content production. It also includes acousticians, audiologists, academics, and those in other disciplines related to audio. The AES is the only worldwide professional society devoted exclusively to audio technology., 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., Wilhelm Franz (1913 in Bremen  1971 in Lahr) was the founder of Elektro-Mess-Technik, a German manufacturer of turntables and professional studio audio equipment. He was an important figure in his field being the designer of the record-playing turntables built by his firm, EMT. The Audio Engineering Society awarded him a posthumous Honorary Membership in 1983, recognizing his impact in the professional sound field not only for his turntables but also for other products like the reverberation units 140, 240 and 250., Elektro - Mess - Technik ( EMT ) is a manufacturer of phonograph turntables and professional audio equipment , including a well - regarded line of artificial reverberation devices beginning with the EMT 140 plate reverb . The company was founded by Wilhelm Franz ., Subject: elektro-mess-technik, Relation: headquarters_location, Options: (A) baden (B) bremen (C) chester (D) germany (E) grafenhausen (F) horn (G) industry (H) kellogg (I) mahlberg
Output (English): mahlberg