Company based in Glasgow, Strathclyde, Scotland and run by Mr. S. Siddiqui that manufactured high end pre-power amplifier combination. Nothing is really known about the company except that it was founded in 1999 as a private limited company and had by 2004 more or less ceased operations and was dissolved in 2007.
Sankyo This Japanese company was one of the pioneers in the manufacture of Compact Cassette recorders and did also make receivers but has exited the audio market (but funnily enough still makes music box movements and DC motors for use in cassette players). Homepage:http://www.sankyo.com
Small Canadian manufacturer of high end valve amplifiers based in Kitchener, Ontario, Canada. Run by designer Tamas Fejerpataky.
Schaak Electronics A chain of consumer electronics stores based in Minneapolis, Minnesota in the USA. Formed a wholly owned subsidary called DLK to manufacture loudspekars that were sold exclusivly through the company's stores. Some of the store brand speakers were real quality units that featured rubber surrounds rather than foam and so on.
Started in 1921 by Georg von Schaub as Schaub-Elektrizitätsgesellschaft and was located in the Charlottenburg district of Berlin, Germany, originally manufacturing various electric equipment but entered the radio receiver market in 1923. The name of the company was changed to G. Schaub Apparatebau Gesellschaft GmbH in 1925 but continued to use plain Schaub as it's trademark and it became one of the better known manufacturers of radios in central Europe. Moved to Pforzheim-Dillweissenstein in 1934 and was taken over by C. Lorenz in 1940 although the company operated mostly independently until the early 50's. Restarted production of loudspeakers and receivers in 1946 or as soon as the occupation forces allowed and sold consumer products initially as Schaub and as later as Schaub-Lorenz, all manufacture of Lorenz CE products was actually handed over to the company in 1950 due to the blockade of Berlin by the Soviet occupation forces, the Schaub company was finally merged with the rest of the C. Lorenz companies in 1958 although the name was used at the least partially up until the sale of the Lorenz consumer division to Nokia in 1988.
Schneider Rundfunkwerke AG The company had its roots in a company founded by Felix Schneider in 1889 in Türkheim in Swabia, Germany, that manufactured industrial woodworking machinery. The company entered the audio business in 1965 by starting the manufacture of radios cabinets etc. and moved into the manufacture of other brown goods soon thereafter and became in particular associated with music systems in the 70's and 80's.
The Schneider company was unusual for West German companies at the time in that they focused squarely on the manufacture of low budget & value products, while the rest of the electronics sector was increasingly focused on higher priced products in response to the ever increasing valuation of the German Mark.
Entered the computer market in 1984 when they started marketing Amstrad PLC computers under their own name in central Europe, initially with notable success, but split up with Amstrad in 1987 when they rejected to distribute the AT compatible computers that the latter company was introducing at the time as they thought they were unsellable, but rather decided to hire the entire European design team from Commodore that had been responsible for designing the PC compatible designs Commodore had introduced a couple of years earlier in addition to the Amiga 2000. This resulted in the introduction of the Euro-PC line of computers in late 1988, an interesting range of designs in some respects, for instance the first PC compatible that had all hardware I/O and set-up functions controlled by the BIOS configuration program rather than having to open the computer and move jumpers around, another unusual BIOS related feature is that you could start the configuration program anytime, even when the OS was running, although innovative this line was not a resounding success but it did pave the way for Schneider to become one of the larger European computer OEM's in the 1990's, but it was already a well-known OEM in the consumer electronics world not the least in the UK where brands like Hinari sold products from the company under their own name.
The company bought the trademark, product lines and factories of the Gebrüder Steidinger company from Thomson in 1988, this was not primarily to get the product lines but rather it appears to be in response to the need for a new trademark for some European markets, notably France, were the Schneider brand was either owned by local companies or there where very well-known companies with that name operating in other business sectors. The old Dual factory in St. Georgen was closed down in 1993 after sales of turntables tumbled and the manufacture of the turntable lineup was taken over by Alfred Fehrenbacher but they are located in the same town as the original Dual Co., the Dual trademark was licensed to the Karstad retail chain in 1996 but by that time Schneider was only using the trademark in France on one hand and for record players internationally.
The company's name was changed to Schneider Electronics AG at some time in the 1990's and different operations where organised into independently run divisions. In the latter years it was perhaps best known locally as a manufacturer of low and mid-range televisions and video recorders but they had started manufacturing those in 1983 but in the early 1990's the Schneider Technologies AG subsidiary developed some innovative TV's for professional usage, the most interesting of these being the laser TV which was based around a solid state RGB laser gun developed in conjunction with Jenoptik, this allows for huge screens without the usual multi-screen/projector setups or the lack of brightness usually associated with projectors. Worsening trade conditions in the late 90's however meant that the company declared itself bankrupt on January 26 2002, TCL International Holdings bought production facilities, stocks and trademarks for 82 million € in September 2002 and used those to form a new company called Schneider Electronics GmbH.
Scientific Audio Electronics (SAE) USA audio electronics manufacturer founded in 1968 by Morris Kessler and Ted Winchester but from 1971 or so owned exclusively by Mr. Kessler, ran into financial problems in the early 80's and was taken over in 1985 by DAK Industries but folded in early 1992 when the parent company went into bankrupcy protection (it eventually went bankrupt altogether in 1994 although the author of this link fails to mention the contractual dispute that triggered the original withdrawal of credit). Had a huge cult following amongst a certain type of audiophiles (and to a certain extent still has) and was in may ways the archetypal 70's American hi-fi manufacturer, along with an array of HUGE amplifiers (usually both in size and power) and the usual tuners, cassette decks etc.., the company had a mind boggling line-up of signal processing equipment ranging from graphic equalisers to specialised noise reduction units. Hard-core fans of the company's products often had large 19" racks filled with equipment, a sight more associated with a recording studio rather than a home system. Mr. Kessler currently runs Amplifier Technologies Inc (ATI). For those that own or are interested in the products of the company there exists a mailing list called SAE Talk that discusses the products of the company. There is an page with some of the early history of the company here.
SD Acoustics A high end loudspeaker manufacturer based in Surbiton, Surrey, England, disappeared in 2002. Specialised in open baffle loudspeaker systems.
Sears, Roebuck & Co. USA based mail order house, it's still in operation and I believe still selling audio equipment, but was in the 50's and 60's one of the biggest if not the biggest seller of home audio gear in America and much of that was sold under their own Sears and Silvertone brands although invariably sourced from North American and Japanese OEM producers. The company is also the current owner of the Eaton's and Viking brands in Canada. Homepage:http://www.sears.com
Sen Not strictly audio but I am including it here since I cannot find any info on this on the web or elsewhere in fact. Situated in Reykjavík in Iceland and operated by Chinese-Icelandic electronic engineer Jón Sen in the 50's and 60's this company was one of the first independent manufacturers of televisions in Europe. Hr. Jón later ran a radio workshop called Rafeindatęki which did in fact provide service for older Sen products but he retired in 2002. (Icelanders are the last European nation to hold onto the paternal naming system so the gentleman is Hr. Jón rather than Mr. Sen).
Sennet (Car / home audio/theatre loudspeakers) See --> Altec Lansing
Seoum There appear from time to time in Europe hi-fi separates made in South-Korea that bear this name, I am assuming these are named after the SK locality of Seoum. The separates are of a better quality than what the Koreans were usually exporting at the time, typically up with Japanese mid priced separates from the same time frame (early - mid 80's) which is unusual since at the time SK was mostly exporting low budget stuff and competing pricewise with Hong Kong. Would like to get further info on the company if anyone out there has it. And BTW the company logo sometimes has the U in the name capped, no idea what that signifies.