Elektromesstechnik (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.

Wilhelm Franz, born in Bremen in 1913, founded Elektromesstechnik Wilhelm Franz K.G. in Berlin in 1938. Two years later Wilhelm's brother, Walter, joined the company. The Allied bombing air raids over Berlin intensified in 1943 and Franz moved to Schuttertal, then, after 1945, to Lahr, in the Schwarzwald (Black Forest) region of south-western Germany. The logo of an arrowhead was chosen as a symbol of the passage of an electric signal in an electronic circuit.

In 1957, EMT introduced the EMT 140 reverberation unit, an electro-mechanical reverberation device that offered an alternative to the spring reverbs and echo chambers of the era. The EMT 140 utilized a very thin 1 meter by 2 meter steel plate suspended within a steel frame. A transducer and a pickup (later two pickups for "stereo") were attached to the steel plate at different locations. When activated, the transducer induced sound waves into the plate. Those direct sound waves traveled through the plate and were, along with the indirect vibrations, sensed by the pickups and then amplified. This signal could then be mixed with the original signal to provide a simulation of a reverberant space. Reverberation times were adjustable between one and five seconds by means of a soft damping felt, which could be moved closer or farther from the steel plate. Like the R80 turntable, the "140" was developed in co-operation with the Rundfunktechnisches Institut and went on to become one of EMT's most successful products, remaining in production for 25 years. A stereo model, the EMT 140 st, was introduced in 1961.

Four EMT 140 were installed at Abbey Road Studios in the late 1950s, and three more added by 1976, for a total of 7. In 2004, the EMT 140 was inducted into the TECnology Hall of Fame, an honor given to "products and innovations that have had an enduring impact on the development of audio technology".

EMT introduced the first commercial digital reverb, the EMT 250 mobile reverberation unit, in 1976. The "250" quickly gained a solid reputation among West Coast recording studios in the US. The physical design of the unit in 1974 by freelance industrial designer Peter Bermes for EMT in close cooperation with EMT Technical Director Karl Otto Bäder and MIT Professor Barry Blesser, who had developed and patented the unit's digital algorithms. The EMT 250 was commonly referred to either "R2D2" because of its iconografic lever-controlled interface, or "Spaceheater" due to its vertical heat sink body made of black anodised aluminium panels and separate U-shaped "chimney", housing all heat-emitting ICs and therefore being painted red. In 2007, the TEC Foundation for Excellence in Audio recognized the EMT 250 as a significant contribution to the advancement of audio technology by inducting it into the TECnology Hall of Fame.

After the war, Franz, in co-operation with the Rundfunktechnisches Institut (Broadcasting Technique Institute), directed by Walter Kuhl, designed the EMT 927 large studio turntable. Introduced in 1951, the "927" is 67 cm wide, 52 cm deep and 21.5 cm high. Its enormous main platter (44 cm) was necessary to play 16" acetate records and was driven by a very large electric motor through a sturdy idler-wheel system. Additionally, it could play the 331⁄3 rpm 12" long-playing records and 7" 45 rpm (RCA-standard) discs. The Danish firm Ortofon provided the tonearm for the 927 ("RF-297") and the first magnetic pickup officially installed by EMT on their turntables. A stroboscope engraved around the acrylic outer platter allowed the fine tuning of the 927's speed, and its quick-start arrangement allowed a remarkably short starting time of less than 500 milliseconds at 33 rpm. The 927 was built in different versions: the "927A", with an optical indicator of the position of the stylus on the grooves, the "927D", a special reference version built with special care and very close tolerances for laboratory use, the "927F" that could accommodate a second tonearm behind the platter, and "927st" stereo version.

The EMT 930 is a large machine as well (49 cm × 39 cm × 17.5 cm), which maintains all the functional characteristics of the larger brother in a more compact package. Its very sturdy cast-metal frame, Kunststoff (Bakelite) main board and idler-wheel drive to the internal rim of its heavy platter gives it peerless sonic qualities. The drive system, start/stop system, brake and speed control are exactly as on the "927". Its bearing, though of a slightly reduced diameter than in the "927", is on par for quality, and it is a "wet" bearing too: it contains 25 ml of special EMT oil, which must be changed every time the turntable is serviced. The preamplifier of the monophonic "930" was the tube "139". The quality and reliability of the EMT machines became rapidly legendary, and the "arrowhead" logo became a symbol of German engineering at its best in professional studio audio equipment, the only possible choice for top radio stations and the phonographic industry.

With its more reasonable size, the "930" was somewhat more economical to build than the "927", making it a very interesting turntable even for smaller studios, but EMT was not building only exceptionally good (and extremely expensive) machines.