Misplaced Pages

#292707

41-423: The diaphone is a noisemaking device best known for its use as a foghorn : It can produce deep, powerful tones, able to carry a long distance. Although they have fallen out of favor, diaphones were also used at some fire stations and in other situations where a loud, audible signal was required. The diaphone horn was based directly on the organ stop of the same name invented by Robert Hope-Jones , creator of

82-565: A combination of cane and synthetics. The dizi , a Chinese transverse flute , has a distinctive kind of reed (a di mo ), which is made from a paper-like bamboo membrane. Musicians originally crafted reeds from cane using simple tools, a time-consuming and painstaking process. Specialized tools for cutting and trimming reeds by hand reduce the time needed to finish a reed. Today, nearly all single-reed instrument players buy manufactured reeds, though many adjust them by shaving or sanding. Some professionals make single reeds from blanks, but this

123-416: A different diameter at other times. The tubes are split into three equal parts and the pieces that are not warped are chosen. A reed made from warped cane will not vibrate consistently on both sides. The split pieces are gouged by machine to remove many layers and drastically decrease thickness, which eases the scraping process for the reed-maker. Finally, the gouged pieces of cane are soaked, shaped on

164-412: A number (most commonly 2, 2.5, 3, 3.5, 4, 4.5, and 5). The strength is determined by a machine that presses against the vamp (the part that includes the tip and the "heart" just behind the tip) of the reed and determines how stiff the reed is. The machine separates the reeds according to hardness. Individual reeds graded with the same strength/hardness will vary in their playing characteristics. Sections of

205-456: A range of about six miles (9.7 km) under optimum conditions. The following installations are still functional and are demonstrated from time to time as tourist attractions. Foghorn All foghorns use a vibrating column of air to create an audible tone, but the method of setting up this vibration differs. Some horns, such as the Daboll trumpet, used vibrating plates or metal reeds ,

246-420: A shaper with razor blades, and allowed to dry before the final steps. The shaped piece of cane is then re-soaked and tied onto a "staple" for oboe reeds or formed on a mandrel for bassoon reeds. Double reeds are tied in place with thread. Finishing both bassoon and oboe reeds requires the reed-maker to scrape along the cane section of the reed with a scraping knife to specific dimensions and lengths depending on

287-577: A similar principle to a modern electric car horn . Others used air forced through holes in a rotating cylinder or disk, in the same manner as a siren . Semi-automatic operation of foghorns was achieved by using a clockwork mechanism (or "coder") to sequentially open the valves admitting air to the horns; each horn was given its own timing characteristics to help mariners identify them. Audible fog signals have been used in one form or another for hundreds of years, initially simply seashell horns , fog bells or gongs struck manually. At some lighthouses ,

328-551: A small cannon was let off periodically to warn away ships, but this was labor-intensive and dangerous. In the United States , whistles were also used where a source of steam power was available, though Trinity House , the British lighthouse authority , did not employ them, preferring an explosive signal. Throughout the 19th century efforts were made to automate the signalling process. Trinity House eventually developed

369-477: A system (the "Signal, Fog, Mk I") for firing a gun-cotton charge electrically. However, the charge had to be manually replaced after each signal. At Portland Bill , for example, which had a five-minute interval between fog-signals, this meant the horns had to be lowered, the two new charges inserted, and the horns raised again every five minutes during foggy periods. Clockwork systems were also developed for striking bells. Stricken bells were developed throughout

410-571: A very different tone and set of harmonics . There are two types of free reeds : framed and unframed. Framed free reeds are used on ancient East Asian instruments such as the Chinese shēng and Japanese shō , ancient Southeast Asian instruments like the Laotian khene , and modern European instruments such as the harmonium or reed organ (consisting of reed pipes ), harmonica , concertina , bandoneón , accordion , and Russian bayan . The reed

451-432: Is a thin strip of material that vibrates to produce a sound on a musical instrument . Most woodwind instrument reeds are made from Arundo donax ("Giant cane") or synthetic material. Tuned reeds (as in harmonicas and accordions ) are made of metal or synthetics. Musical instruments are classified according to the type and number of reeds. The earliest types of single-reed instruments used idioglottal reeds , where

SECTION 10

#1732790238293

492-438: Is generally measured on a scale of 1 through 5 from softest to hardest. This is not a standardized scale and reed strengths vary by manufacturer. The thickness of the tip and heel and the profile in between affect the sound and playability. Pieces of cane of different density or stiffness, even if cut with the same profile, will respond differently due to those differences. The cane used to make reeds for single-reed instruments

533-741: Is grown in the southern coastal regions of France and Spain and, in the last 30 years, in the Cuyo area of Argentina. After the cane is cut it is placed in direct sunlight for about a month to dry. The cane is rotated regularly to ensure even and complete drying. Once dry, the cane is stored in a warehouse. As production requires it, cane is taken to a factory's cutting department, where it is cut into tubes graded by diameter and wall density. The tubes are cut into splits and made into reed blanks. Blanks are tapered and profiled into reeds using blades or CNC machines. Completed reeds are graded for strength by machine. Double reeds are used on many instruments, such as

574-437: Is made from cane, willow, brass or steel, and is enclosed in a rigid frame. The pitch of the framed free reed is fixed. The ancient bullroarer is an unframed free reed made of a stone or wood board tied to a rope that is swung around through the air to make a whistling sound. Another primitive unframed free-reed instrument is the leaf (the bilu ), used in some traditional Chinese music ensembles. A leaf or long blade of grass

615-513: Is stretched between the sides of the thumbs and tensioned slightly by bending the thumbs to change the pitch. The tone can be modified by cupping the hands to provide a resonant chamber. Most woodwind instrument reeds are made from cane , but there are synthetic reeds for clarinet, saxophone, double reed instruments, and bagpipes. Synthetic reeds are more durable and do not need to be moistened prior to playing. Recently, synthetic reeds have been made from synthetic polymer compounds, and from

656-415: Is time-consuming and can require expensive equipment. Among double reed players, advanced and professional players typically make their own reeds, while beginners and students often buy reeds, either from their teachers or from commercial sources. The playing characteristics of cane reeds are susceptible to changes in temperature and humidity. Manufacturers produce reeds in different strengths, indicated by

697-660: The Daboll trumpet for the American lighthouse service, though it was not universally adopted. A few Daboll trumpets remained in use until the mid-20th century. In the United Kingdom , experiments to develop more effective foghorns were carried out by John Tyndall and Lord Rayleigh , amongst others. The latter's ongoing research for Trinity House culminated in a design for a siren with a large trumpet designed to achieve maximum sound propagation (see reference for details of

738-485: The International Association of Lighthouse Authorities . Fog signals have also been used on railway lines since the middle of the 19th century to indicate to warn of disabled trains, work parties, or other hazards on the line ahead. Small explosive detonators or torpedoes are placed on the track, and detonated by the pressure of the wheels of the oncoming train. British writer Jennifer Lucy Allan

779-429: The United Kingdom , already a major supplier of Fresnel lenses and other equipment to lighthouse authorities. In use, the diaphone was generally found to be reliable and suffered little from wear, as the lightweight piston floated on a cushion of air during oscillation. Such wear as did occur tended to happen as a result of the piston becoming loose: as the pistons were custom-made and the design to some degree affected

820-487: The Wurlitzer organ. Hope-Jones' design was based on a piston that was closed only at its bottom end and had slots, perpendicular to its axis, cut through its sides; the slotted piston moved within a similarly slotted cylinder. Outside of the cylinder was a reservoir of high-pressure air. Initially, high-pressure air would be admitted behind the piston, pushing it forward. When the slots of the piston aligned with those of

861-425: The oboe , oboe d'amore , English horn , bass oboe , heckelphone , bassoon , contrabassoon , sarrusophone , shawm , bagpipes , nadaswaram and shehnai and others . The two reeds vibrate against each other and not against a mouthpiece. In the case of the crumhorn , bagpipes , and Rauschpfeife , a reed cap encloses the reeds and the reeds do not contact the player's mouth. Double reed manufacturing begins

SECTION 20

#1732790238293

902-889: The "Improved Type F" or later as the "F2T", was particularly common in installations on the West Coast of the United States and in lightvessels. Installations in Europe generally used single-tone diaphones. Rodney Northey sold the Diaphone Signal Co. in 1932, when it was bought by a Buffalo, New York company, Deck Brothers, working under contract for the United States Lighthouse Service . This company still exists, although it no longer manufactures diaphones. The European manufacturing rights were obtained by Chance Brothers of Birmingham in

943-526: The 1800s with the use of a governor, including the use of a giant triangle of 4 ft long sides in Maine in 1837. Ships were required to carry bells, with an exemption for Turkish ships because Islam forbade the use of bells. Captain James William Newton claimed to have been the inventor of the fog signalling technique using loud and low notes. The first automated steam -powered foghorn

984-584: The Commissioners of Light Houses for the Bay of Fundy for installation on Partridge Island . While the Commissioners initially rejected Foulis's plan, one commissioner eventually encouraged Foulis to submit detailed plans to the Commission. For reasons unknown, the plans were given to another Canadian engineer, T. T. Vernon Smith , who officially submitted them to the Commissioners as his own. The foghorn

1025-600: The Dutch broadcaster VPRO aired a live foghorn concert on national radio composed by Marnie Bjornson, relaying the sound of the foghorns in Emden , Calais , Nieuwpoort , Scheveningen , Den Helder , Lelystad , Urk , Marken and Kornwerderzand , mixed with studio music by sound artist Alvin Curran . Since automation of lighthouses became common in the 1960s and 1970s, most older foghorn installations have been removed to avoid

1066-535: The Trials of Fog Signals ), installed in Trevose Head Lighthouse , Cornwall in 1913. One reporter, after hearing a Brown steam-powered siren for the first time, described it as having "a screech like an army of panthers, weird and prolonged, gradually lowering in note until after half a minute it becomes the roar of a thousand mad bulls, with intermediate voices suggestive of the wail of a lost soul,

1107-584: The cylinder, air passed into the piston, making a sound and pushing the piston back to its starting position, whence the cycle would repeat. A modification of Hope-Jones' design was patented by John Pell Northey, head of the Northey Co. Ltd. of Toronto, Ontario, Canada, which manufactured pumps and small gasoline engines. Northey added a secondary compressed air supply to the piston in order to power it during both its forward and reverse strokes and thus create an even more powerful sound. The entire horn apparatus

1148-445: The individual sound characteristics of the signal, the manufacturers supplied two spare pistons with each diaphone. The majority of diaphone installations were removed or became disused during the 1960s and 1970s. This was partly a result of automation of lighthouses, but it was also found that modern diaphragm horns would produce similar levels of volume to a diaphone while requiring much smaller and less powerful compressors. By 1983,

1189-556: The last two-tone "F2T" type in full-time operation in the United States was at Edgartown , Martha's Vineyard . A few survive in working condition in lighthouses around the world. This considerably smaller device was produced by the Gamewell Corporation, of Newton, Massachusetts , for use as a municipal alarm , especially at fire stations, to alert firefighters and the public during emergencies. Many Gamewell diaphone systems remain in use today. The Gamewell diaphone has

1230-501: The moan of a bottomless pit and the groan of a disabled elevator." One of the first automated fog bells was the Stevens Automatic Bell Striker. Some later fog bells were placed under water, particularly in especially dangerous areas, so that their sound (which would be a predictable code, such as the number "23") would be carried further and reverberate through the ship's hull. For example, this technique

1271-467: The mouthpieces of clarinets and saxophones . The back of the reed is flat and is placed against the mouthpiece. These reeds are roughly rectangular in shape and taper towards the thin tip, which is rounded to match the curve of the mouthpiece tip. All single reeds are shaped similarly but vary in size to fit each instrument's mouthpiece. Reeds designed for the same instrument look roughly identical, but vary in thickness ("hardness" or "strength"). Hardness

Diaphone - Misplaced Pages Continue

1312-503: The need to run the complex machinery associated with them, and have been replaced with electrically powered diaphragm or compressed air horns . Activation is completely automated: a laser or photo beam is shot out to sea, and if the beam reflects back to the source (i.e. the laser beam is visible due to the fog), the sensor sends a signal to activate the foghorn. In many cases, modern navigational aids, including GPS , have rendered large, long-range foghorns completely unnecessary, according to

1353-406: The piston decelerating as the air supply was cut. As this low-frequency sound could carry farther, Northey's son Rodney redesigned the "Type F" model to sustain the second low tone, creating the familiar two-tone fog signal, commonly used in lighthouses and lightvessels in the United States and Canada (as well as in a famous series of radio commercials for Lifebuoy soap ). This version, known as

1394-476: The reed style and the musician's preference. Bassoon and oboe reeds are finished when the reeds play in tune or can make a sufficient "crow"-like noise. Quadruple reed instruments have four reeds, two on top and two on bottom. Examples of this include an archetypal instrument from India , the shehnai , as well as the pi from Thailand , and the Cambodian sralai . Having four reeds instead of two produces

1435-400: The same way as that of single reeds. Arundo donax cane is collected, dried, processed, cut to manageable sizes, and separated into various diameters. The most common diameters for American-style oboe reeds are: 9.5–10 mm (0.37–0.39 in), 10–10.5 mm (0.39–0.41 in), and 10.5–11 mm (0.41–0.43 in). Many American oboists prefer one diameter at one time of the year and

1476-427: The vibrating reed is a tongue cut and shaped on the tube of cane. Much later, single-reed instruments started using heteroglottal reeds , where a reed is cut and separated from the tube of cane and attached to a mouthpiece of some sort. By contrast, in an uncapped double reed instrument (such as the oboe and bassoon), there is no mouthpiece; the two parts of the reed vibrate against one another. Single reeds are used on

1517-758: Was awarded a PhD by the University of the Arts London in 2019 for her thesis on Fog tropes : a social and cultural history of the foghorn and subsequently published a book: The Foghorn's Lament: the Disappearing Music of the Coast . "The Atmosphere in Relation to Fog-Signaling I"  . Popular Science Monthly . Vol. 6. March 1875. ISSN   0161-7370 – via Wikisource . Reed (music) A reed (or lamella )

1558-474: Was constructed at Partridge Island in 1859 as the Vernon-Smith horn. After protest by Foulis and a legislative inquiry, Foulis was credited as the true inventor, but he never patented or profited from his invention. The development of fog signal technology continued apace at the end of the 19th century. During the same period an inventor, Celadon Leeds Daboll , developed a coal-powered foghorn called

1599-415: Was driven by a compressor . To manufacture the new equipment, Northey set up the Diaphone Signal Co. at Toronto in 1903. It manufactured a range of diaphone models: the large "Type F", which created a tone of about 250 Hz , found worldwide use as a fog signal , especially in lighthouses . The mechanism of the diaphone created a noticeable low-frequency "grunt" at the end of each note produced, caused by

1640-407: Was invented by Robert Foulis , a Scotsman who emigrated to Saint John , New Brunswick , Canada. Foulis is said to have heard his daughter playing the piano in the distance on a foggy night, and noticed the low notes were more audible than the higher notes: he then designed a device to produce a low-frequency sound, as well as a code system for use with it. Foulis repeatedly presented his concept to

1681-455: Was used at White Shoal Light (Michigan) . This was an earlier precursor to RACON . From the early 20th century an improved device called the diaphone , originally invented as an organ stop by Robert Hope-Jones , and developed as a fog signal by John Northey of Toronto , became the standard foghorn apparatus for new installations. Diaphones were powered by compressed air and could emit extremely powerful low-frequency notes. In 1982,

Diaphone - Misplaced Pages Continue

#292707