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تاريخ التسجيل : 02/10/2009
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 | | موضوع: Polymers in Percussion Instruments الثلاثاء 9 أكتوبر 2012 - 12:19 | |
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Drums | Timpani | Xylophone and Marimba | Sticks and MalletsPercussion instruments have such variety there's no way we can show them all here. The main materials used for getting volume of sound are metal (which is not a polymer) wood, and stretched animal skin or plastic. Here we will show you a few of the more popular types of percussion. Some of them are used to add rhythm or volume to the orchestra or band, and others are actually used to play melodic parts. And some do both.Drums
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Drums come in every shape and size you can think of and from every culture. Here are just some examples. Through the ages drum heads have usually been made from animal skinstretched over a round opening. The resonating body of the drum is normally made form some kind of wood.
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 Marching Drums - a set of
quads, a bass drum, a snare
drum and a tenor drum |
These more modern drums have heads on both ends made from polyethylene and polyester (Mylar) and lots of metal hardware used for tightening and tuning the heads. The tighter the head, the higher the pitch it makes. Some really high-tech, high-tension snare drums have heads made from Kevlar - which is a type of nylon known as an aramid.Snare drums also have a loud popping sound caused by thin cords or "snares" which are pulled tightly across the bottom head. The snares vibrate against the head when the drum is hit, giving a distinctive high rattle. Snares were traditionally made of a material called "catgut" - though it is not made from cats at all. The actual material was made from sheep gut (a type of protein), like violin strings used to be. But now snares are nylon. The toms in a trap set have no snares so their sound is more mellow and they are usually tuned to certain notes. The more toms you have, the better your drum solo will sound. The marching equivalent of this is the tenor drums or the quads, which give the band's drum cadences a nice melodic feel. Tenor drums and quads have heads made from thin Mylar which gives a nice "bouncy" sound. |
The bass drum is made to sound BIG, and - like toms and snares - may come in different sizes. And, like all the others, the bass has heads made of polyethylene. But this big concert bass drum has a head made of heavy paper formed from cellulose - a sort of synthetic skin - if you can believe that. This is the huge drum used to give the orchestra that extra "oomph!"TimpaniSpeaking of the orchestra, these big guys are drums very commonly found there, but they're kind of special so they get their own section. Timpani - also known as "kettle drums" due to their appearance as giant stew pots - are more a part of the melody than most other drums. They can be tuned to certain pitches like other drums, but the notes sound very distinct, so distinct that when you hear the timpani play you can hum along with them. Think of the drums at the opening music used in the movie 2001: a Space Odyssey, or the drums in the popular Olympics theme music. In both cases they are the deep resonating timpani.The large polyethylene heads of the timpani are usually tuned to the first note and the fifth note of the key in which the orchestra is playing. This way they can add a big, yet melodic, bass line that sounds somehow very majestic and powerful.Xylophone and MarimbaThe xylophone and the marimba are formed by wooden bars of different lengths to create the different pitches. These instruments also have resonators - metal tubes - which amplify the pitches. On older marimbas the resonators were made from hollowed out gourds - a form of cellulose. Now they are made of aluminum which is carefully tuned to bring out the specific pitch of the wooden bar above it.Sticks and MalletsDrumsticks are usually made from wood, though some of them also have tough nylon tips. They can also be fancy with rubber gripping material or decorative coatings made from various plastics. They may also be painted cool colors.Mallets are used for all kinds of percussion, from tenor drums to chimes. A lot of them are wood. Many others have ends made from wool fibers compressed into hard felt. They can have handles made from wood or tough plastic like Delrin with rubber grips. And the mallets used for chimes are a very hard clear plastic called polymethylmethacrylate - often sold as Lucite. | |
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