jazz的英文介绍

jazzIIntroductionJazz,typeofmusicfirstdevelopedbyAfricanAmericansaroundthefirstdecadeofthe20thcenturythathasanidentifiablehistoryanddistinctstylisticevolution.Jazzgrewupalongsidethebluesandpopularmusic,andallthesegenresoverlapinmanyways.However,criticsgenerallyagreeaboutwhetherartistsfallsquarelyinonecamporanother.IICharacteristicsSinceitsbeginningsjazzhasbranchedoutintosomanystylesthatnosingledescriptionfitsallofthemaccurately.Afewgeneralizationscanbemade,however,bearinginmindthatforallofthem,exceptionscanbecited.Performersofjazzimprovisewithintheconventionsoftheirchosenstyle.Typically,theimprovisationisaccompaniedbytherepeatedchordprogressionofapopularsongoranoriginalcomposition.Instrumentalistsemulateblackvocalstyles,includingtheuseofglissandi(slidingmovementsthatsmoothlychangethepitch),nuancesofpitch(includingbluenotes,the“bent”notesthatareplayedorsungslightlylowerthanthemajorscale),andtonaleffectssuchasgrowlsandwails.Instrivingtodevelopapersonalsound,ortonecolor(anidiosyncraticsenseofrhythmandformandanindividualstyleofexecution),performerscreaterhythmscharacterizedbyconstantsyncopation(theplacingofaccentsinunexpectedplaces,usuallyontheweakerbeat)andbyswing.Swingcanbedefinedasasensationofmomentuminwhichamelodyisalternatelyheardtogetherwith,thenslightlyatvariancewith,theregularbeat.Writtenscores,ifpresent,areoftenusedmerelyasguides,providingstructurewithinwhichimprovisationoccurs.Thetypicalinstrumentationbeginswitharhythmsectionconsistingofpiano,stringbass,drums,andoptionalguitar,towhichmaybeaddedanynumberofwindinstruments.Inbigbandsthewindinstrumentsaregroupedintothreesections:saxophones,trombones,andtrumpets.Althoughexceptionsoccurinsomestyles,mostjazzisbasedontheprinciplethataninfinitenumberofmelodiescanfitthechordprogressionsofanysong.Themusicianimprovisesnewmelodiesthatfitthechordprogression,whichisrepeatedagainandagainaseachsoloistisfeatured,forasmanychorusesasdesired.Althoughpieceswithmanydifferentformalpatternsareusedforjazzimprovisation,twoformalpatternsinparticulararefrequentlyfoundinsongsusedforjazz.OneistheAABAformofpopular-songchoruses,whichtypicallyconsistsof32measuresin¹meter,dividedintofour8-measuresections:sectionA,arepetitionofsectionA,sectionB(the“bridge”or“release,”oftenbeginninginanewkey),andarepetitionofsectionA.Thesecondform,withrootsdeepinAfricanAmericanfolkmusic,isthe12-barbluesform.Unlikethe32-barAABAform,bluessongshaveafairlystandardizedchordprogression.IIIOriginsJazzisrootedinthemingledmusicaltraditionsofAfricanAmericans.TheseincludetraitssurvivingfromWestAfricanmusic;blackfolkmusicformsdevelopedintheAmericas;Europeanpopularandlightclassicalmusicofthe18thand19thcenturies;andlaterpopularmusicformsinfluencedbyblackmusicorproducedbyblackcomposers.AmongthesurvivingAfricantraitsarevocalstylesthatincludegreatfreedomofvocalcolor;atraditionofimprovisation;call-and-responsepatterns;andrhythmiccomplexity,bothinthesyncopationofindividualmelodiclinesandintheconflictingrhythmsplayedbydifferentmembersofanensemble.Blackfolkmusicformsincludefieldhollers,rowingchants,lullabies,andlater,spiritualsandblues(seeAfricanAmericanMusic).Europeanmusiccontributedspecificstylesandforms:hymns,marches,waltzes,quadrilles,andotherdancemusic,aswellaslighttheatricalmusicandItalianoperaticmusic.Europeanmusicalsointroducedtheoreticalelements,inparticular,harmony,bothasavocabularyofchordsandasaconceptrelatedtomusicalform.(MuchoftheEuropeaninfluencewasabsorbedthroughprivatelessonsinEuropeanmusic,evenwhentheblackmusicianssotrainedcouldonlyfindworkinseedyentertainmentdistrictsandonMississippiriverboats.)Black-influencedelementsofpopularmusicthatcontributedtojazzincludethebanjomusicoftheminstrelshows(derivedfromthebanjomusicofslaves),thesyncopatedrhythmicpatternsofAfrican-influencedLatinAmericanmusic(heardinsouthernU.S.cities),thebarrelhousepianostylesoftavernmusiciansintheMidwest,andthemarchesplayedbyblackbrassbandsinthelate19thcentury.Neartheendofthe19thcentury,anotherinfluentialgenreemerged.Thiswasragtime,acomposedmusicthatcombinedmanyelements,includingsyncopatedrhythms(frombanjomusicandotherblacksources)andtheharmoniccontrastsandformalpatternsofEuropeanmarches.After1910bandleaderW.C.Handytookanotherinfluentialform,theblues,andbrokeitsstrictoraltraditionbypublishinghisoriginalbluessongs.(Favoredbyjazzmusicians,Handy’ssongsfoundoneoftheirgreatestinterpretersinthe1920sinbluessingerBessieSmith,whorecordedmanyofthem.)Themergingofthesemultipleinfluencesintojazzisdifficulttoreconstructbecauseitoccurredbeforetheexistenceofrecording,whichhasprovidedvaluabledocumentation.Ofcourse,individualmusicianshadvaryingbackgroundsandfewpeopleweredirectlyexposedtoalloftheseinfluences.Forexample,mostjazzartistswereandarecitydwellersandmighthaveonlyknownruralblackformsindirectly.IVHistoryMostearlyjazzwasplayedinsmalldancebandsorbysolopianists.Besidesragtimeandmarches,therepertoireincludedallkindsofpopulardancemusicandblues.Thebandstypicallyplayedatpicnics,weddings,parades,andfunerals.Characteristically,thebandsplayeddirgesonthewaytofune