Japanese company founded in 1978 by inventor Kazuo Ishi but he had invented and patented a new type of electrolytic capacitor where the electron flow between cathode and anode is improved by the addition of graphite particles to the electrolyte. This gives the capacitor is much less self-noise than with a normal cap, higher possible operating frequencies and the working life is extended to 25+ years since there is less loss of electrolyte due to heating etc.
The addition of graphite brings some problems with it though, construction is more difficult since the real care has to be taken in doping the electrolyte otherwise it will short which meant that these capacitors were more expensive that standard electrolytic caps and in some configurations much more so. This meant that the market for the devices was pretty much limited to on one hand high end communications equipment that needed the improved frequency operating range that these caps offered and on the other high end audio products where the improved self-noise characteristics did in some cases bring quite extraordinary benefits.
Jelmax initially worked with a smaller subcontractor to manufacture the devices and sold them under their own Black Gate trademark but in 1988 managed to get a manufacturing contract with Rubycon that meant an improved supply and prices alongside top notch quality. While the capacitors gained a cult following initially amongst a small sector of amplifier manufacturers they did not really enter the vision of the DIY enthusiast until the advent of the Internet and even then they were controversial since they were very expensive and only performed well in certain types of circuits, but in reality similar specialist capacitors like oil filled ones are even more expensive and when the Black Gates worked they showed large performance gains.
The non-polarised variants of the Black Caps were also sold in some countries as Super E-Caps up until the late 90's or so, but in 2005 it was announced that production would cease since Rubycon no longer considered the quantities involved to be high enough to be profitable, production closed down in 2006 and the company was closed in 2007 after all existing stocks had been depleted and their website appears to have been cybersquatted.
A number of electronics parts retailers still have some of their products in stock in the summer of 2010, in particular lower capacitance values but bigger values useful for amplifier outputs or power supplies are all long gone.
Loudspeaker manufacturer based in Los Angeles, California, USA and founded in March 1975 by Tom Jennings that had been the head of marketing for JBL in the late 60’s and early 70’s. Initial product line was called “Contrara Group” was introduced that summer and the company made quite a splash initially with an advertising campaign in national magazines such as Popular science and the New Yorker and these appear to have sold well since they do turn up for sale quite often, the company introduced a line of amplifiers the next year, but they appear to have been in production for only a couple of years.
Jin Qian Li Chinese trading company active in the 1990's, sold professional audio products such as amplifiers and karaoke machines under the JQN brand, these were all sourced from local OEM's. The company merged with pro-audio manufacturers Yuantian and Liangyin to form Guang Zhou HuiYing Electronics in 2002.
JMI Loudspeaker manufacturer based in Vancouver, British Columbia, Canada, some of their bigger models were well liked at the time and one or 2 models are still sought after by local collectors. Timeline is not known but in 1972 they had one fairly small model out that appears to have been known as just the "JMI loudspeaker" but later on they had a number of models and the brand was by then known as JMI Mercer, seem to have disappeared before 1980 but that is not known for certain either.
John Gallas A gentleman based in Los Angeles, California, USA that manufactured acoustic bass traps under the Acoustic Solutions brand between ca. 1992 and 2002. This was just a part time operation, but we think Mr. Gallas’s main profession was teaching at college or university level and that he has since retired. The traps were small cylindral things that were supposed to go into the corners behind the speakers and not in front as most are, and were slightly unusual in that they really only worked with low bass and thus only worked in some rooms, but where they did work they were better than standard bass traps, at the time anyway. They were also quite expensive at 750 USD per pair in 1996.
Company founded in 1961 in California, USA by George Aratani who provided the finance and Hiroshi William Kasuga, an American businessman of Japanese descent that had worked with A&A trading Co. and Radio Shack to procure electronic CE and communications equipment from Japanese OEM's. The name Kenwwod was simply chosen since it would have a similar pronunciation in both Japanese and English and other well-known brands existed in the USA at the time that started with Ken such as Kenmore and Kenworth, Ken in Japanese means province or canton BTW.
The company initially worked with a number of Japanes OEM’s but quickly settled into a relationship with the Trio company and over the years the co-operation between the two had become close with the American company often taking part in the specification process. Kenwood was in fact so successful as a marketing concern that it became much better known than Trio in the Americas, even though Trio branded products were generally available there, in the end Trio bought into the Kenwood Electronics company in the 1970’s, in 1981 decided to rename itself Kenwood in order to have only one brandname worldwide and bought the naming rights from the USA company and in 1986 bought the Kenwood Elctronics Inc. company outright and merged it into its own North American concern and the combined operation is now known as Kenwood U.S.A.
Please note that the original name of the Trio corporation was Kasuga Radio Co. Ltd., there is no connection between the company name and that of William Kasuga’s family name, it is just a not very unlikely coincidence given that Kasuga is a fairly common Japanese last name..
Keroes Enterprises Company founded by Herbert I. Keroes in Philadelphia, Pennsylvania, USA in the latter half of the 50’s. Initially the company was used for the IP that Mr. Keroes generated in regards to the Acrosound company that he owned, but copyrights and patents filed from the late 50’s were assigned to KE and not Acro, some of the later amplifier designs from that company also featured a K logo in addition to the Acrosound name printed onto them
It was believed that KE had been purely a holdings company but recently there have showed up a number of transformers for sale that bear the Keroes Enterprises name, and in addition to that we have found a reference to KE owning or rather using the Acrosound brand later on but that might be a misunderstanding. However we have no idea if the transformers made by KE were made by Acro or are from after that company went bust.
Keswick Audio Research A mid/high end loudspeaker manufacturer based in Ferrybridge, Knottingley, Yorkshire in the UK and run by Dean S. Hartley, timeline is uncertain but Mr. Hartley joined Monitor Audio in 1998 after the takeover of that company by Dave Collins.
Kinergetics Research US based manufacturer of high end audio separates including CD players and amplifiers. Actually started up in 1971 by Tony DiChiro and Ken Cowans as a R&D shop specialising in cryogenic refrigerators and deep sea diving equipment, branched into the manufacture of specialised diving equipment for the oil industry in 1973 and in 1974 set up a electronics manufacturing division that specialised in audio and video products for professional undervater applications. In 1980 they introduced the Compusound loudspeaker that featured acoustic processing electronics, but despite the name the processing electronics where analogue BBD's and since these where quite successful in the market the company turned it's attention to the manufacture of home hi-fi products and by the late 80's had become a pure home audio company. KR was wound down by it's owners in 2000 as it was not thought it would archive profitability in the foreseeable future. For repairs in the USA try this company, they should be able to get you in contact with an ex engineer or try contacting the gentleman here below who is a former head tech for the company Fred Pham, 26103 Belle Porte Ave. Apt D, Harbor City, CA 90710. Tel : (310) 534-5336 or (310) 408-7597...
Small British company founded by Peter Hawkins that started out in 1991 and made amplification products and DAC's, but stopped production in 1995, Mr. Hawkins went on to found a new company in 1997 called Goingon did prowise support for Kinshaw products and he now has a company called Hawkshead that acts mostly as an electronic design consultancy but does provide some support for Kinshaw customers including spares, repairs and upgrades. We have minimal information on the Kinshaw RIAA Preamplifiers. - Mr. Hawkins Kinshaw pages
Kraco Company was founded in 1954 in Compton, Califoria, USA and sold auto sound accessories. Company is still based in Compton but is currently called Kraco Enterprises Inc and only manufactures floormats for cars. Homepage:http://www.kraco.com.
Kyocera Originally Kyoto Ceramics, this is a Japanese manufacturer of ceramics, electronic parts and consumer electronics primarily as an OEM. Manufactured Hi-fi under this name after they merged with Cybernet in 1982, some of their products were really innovative and benefited greatly from the company's research into advanced ceramic technologies, in particular turntables and cassette decks, by the latter half of the 80's this gave them a reputation not dissimilar to what Nakamichi had at the time, but the line suffered from distribution problems as the hi-fi market in particular and consumer markets in general were not really the company's forte and they exited this market segment shortly thereafter. The company also acted as an manufacturer for a host of other brands such as aforementioned Nakamichi. Homepage:http://global.kyocera.com.