Txhua leej txhua tus paub tias cov hlau nplaum xav tau hauv cov khoom siv hluav taws xob xws li hais lus, hais lus, thiab lub mloog pob ntseg, ces lub luag haujlwm twg cov hlau nplaum ua si hauv cov khoom siv electroacoustic? Dab tsi cuam tshuam qhov kev ua tau zoo ntawm cov hlau nplaum rau ntawm lub suab tso zis zoo? Cov hlau nplaum twg yuav tsum tau siv rau hauv cov neeg hais lus sib txawv?
Tuaj thiab tshawb xyuas cov neeg hais lus thiab cov hlau nplaum hais lus nrog koj hnub no.
Lub luag haujlwm tseem ceeb ntawm lub luag haujlwm ua lub suab hauv lub suab yog tus hais lus, feem ntau hu ua tus hais lus. Txawm hais tias nws yog lub tso suab lossis lub mloog pob ntseg, cov khoom tseem ceeb no yog qhov tseem ceeb. Tus hais lus yog ib hom kev hloov khoom siv uas hloov cov teeb liab hluav taws xob rau hauv acoustic signals. Kev ua tau zoo ntawm tus neeg hais lus muaj txiaj ntsig zoo rau lub suab zoo. Yog tias koj xav nkag siab txog tus hais lus magnetism, koj yuav tsum xub pib nrog lub suab nrov ntawm tus neeg hais lus.
Tus neeg hais lus feem ntau yog tsim los ntawm ntau yam tseem ceeb xws li T hlau, hlau nplaum, lub suab coil thiab diaphragm. Peb txhua tus paub tias cov hlau nplaum yuav raug tsim los ntawm cov hlau nplaum, thiab lub zog ntawm qhov tam sim no cuam tshuam rau lub zog ntawm cov hlau nplaum (kev taw qhia ntawm cov hlau nplaum ua raws li txoj cai sab xis). Ib tug sib nqus teb yog generated. Qhov no magnetic teb interacts nrog lub magnetic teb generated los ntawm cov hlau nplaum ntawm tus hais lus. Qhov kev quab yuam no ua rau lub suab coil vibrate nrog lub zog ntawm lub suab tam sim no hauv tus neeg hais lus lub suab sib nqus. Lub diaphragm ntawm tus hais lus thiab lub suab coil txuas ua ke. Thaum lub suab coil thiab lub diaphragm ntawm tus neeg hais lus co ua ke los thawb cov huab cua nyob ib puag ncig kom vibrate, tus hais lus ua suab.
Nyob rau hauv cov ntaub ntawv ntawm tib lub magnet ntim thiab tib lub suab coil, qhov kev ua tau zoo ntawm cov hlau nplaum muaj qhov cuam tshuam ncaj qha rau lub suab zoo ntawm tus hais lus:
-Qhov ntau dua qhov sib nqus flux ntom ntom (sib nqus induction) B ntawm cov hlau nplaum, qhov muaj zog dua qhov ua haujlwm ntawm lub suab membrane.
-Qhov ntau dua qhov sib nqus flux ceev (magnetic induction) B, lub zog ntau dua, thiab siab dua SPL suab siab (rhiab heev).
Lub mloog pob ntseg rhiab heev yog hais txog lub suab siab uas lub pob ntseg tuaj yeem tawm thaum taw tes rau sine yoj ntawm 1mw thiab 1khz. Chav tsev ntawm lub suab siab yog dB (decibel), qhov siab dua lub suab, qhov ntim ntau dua, yog li qhov siab dua qhov siab, qhov qis impedance, qhov yooj yim dua rau lub mloog pob ntseg tsim suab.
-Qhov ntau dua qhov sib nqus flux ceev (magnetic induction intensity) B, qhov qis Q tus nqi ntawm tag nrho cov neeg hais lus zoo.
Q tus nqi (qualityfactor) yog hais txog ib pawg ntawm qhov tsis sib xws ntawm tus neeg hais lus damping coefficient, qhov twg Qms yog damping ntawm lub tshuab tshuab, uas qhia txog kev nqus thiab kev siv lub zog hauv kev txav ntawm cov lus hais. Qes yog qhov damping ntawm lub zog hluav taws xob, uas yog qhov tseem ceeb hauv kev siv lub zog ntawm lub suab coil DC tsis kam; Qts yog tag nrho damping, thiab kev sib raug zoo ntawm ob qho saum toj no yog Qts = Qms * Qes / (Qms + Qes).
-Qhov ntau dua qhov sib nqus flux ntom ntom (magnetic induction) B, qhov zoo dua qhov hloov pauv.
Kev hloov pauv tuaj yeem nkag siab tias "kev teb sai" rau lub teeb liab, Qms kuj siab heev. Lub mloog pob ntseg nrog cov lus teb zoo ib ntus yuav tsum teb sai li sai tau thaum lub teeb liab tuaj, thiab lub teeb liab yuav nres sai li sai tau thaum nws nres. Piv txwv li, kev hloov ntawm cov hlau lead mus rau pawg yog pom tseeb tshaj plaws nyob rau hauv nruas thiab symphonies ntawm loj scenes.
Muaj peb hom kev hais lus hlau nplaum nyob rau hauv kev ua lag luam: aluminium nickel cobalt, ferrite thiab neodymium hlau boron, Cov hlau nplaum siv hauv electroacoustics yog cov hlau nplaum neodymium thiab ferrites. Lawv muaj nyob rau hauv ntau qhov ntau thiab tsawg ntawm cov nplhaib lossis cov duab disc. NdFeB feem ntau siv hauv cov khoom lag luam siab. Lub suab tsim los ntawm cov hlau nplaum neodymium muaj lub suab zoo, lub suab zoo elasticity, zoo suab ua haujlwm, thiab qhov tseeb suab thaj chaw. Cia siab rau qhov ua tau zoo ntawm Honsen Magnetics, me me thiab lub teeb neodymium hlau boron pib maj mam hloov cov ferrites loj thiab hnyav.
Alnico yog cov hlau nplaum ntxov tshaj plaws siv hauv cov neeg hais lus, xws li cov neeg hais lus hauv xyoo 1950 thiab 1960s (paub tias tweeters). Feem ntau ua rau hauv cov lus sib nqus sab hauv (sab nraud hom magnetic kuj muaj). Qhov tsis zoo yog tias lub zog me me, qhov ntau zaus yog nqaim, nyuaj thiab nkig, thiab kev ua haujlwm tsis yooj yim heev. Tsis tas li ntawd, cobalt yog ib qho khoom siv tsis tshua muaj, thiab tus nqi ntawm aluminium nickel cobalt yog qhov siab. Los ntawm kev xaav ntawm cov nqi kev ua tau zoo, kev siv cov txhuas nickel cobalt rau cov hlau nplaum hais lus yog me me.
Ferrites feem ntau yog ua rau sab nraud sib nqus lus. Qhov kev ua tau zoo ntawm ferrite sib nqus yog qhov tsawg, thiab qee qhov ntim yuav tsum tau ua kom tau raws li lub zog tsav ntawm tus neeg hais lus. Yog li ntawd, nws feem ntau yog siv rau lub suab hais lus loj dua. Qhov zoo ntawm ferrite yog tias nws yog pheej yig thiab siv tau; qhov tsis zoo yog qhov ntim loj, lub zog me me, thiab qhov ntau zaus yog nqaim.
Cov khoom sib nqus ntawm NdFeB yog qhov zoo tshaj plaws rau AlNiCo thiab ferrite thiab tam sim no yog cov hlau nplaum siv tshaj plaws ntawm cov neeg hais lus, tshwj xeeb tshaj yog cov neeg hais lus siab. Qhov zoo dua yog tias nyob rau hauv tib lub sib nqus flux, nws qhov ntim me me, lub zog loj, thiab qhov ntau zaus yog dav. Tam sim no, HiFi headphones yeej siv cov hlau nplaum zoo li no. Qhov tsis zoo yog vim qhov tsis tshua muaj ntiaj teb cov ntsiab lus, cov khoom siv tus nqi siab dua.
Ua ntej tshaj plaws, nws yog ib qho tsim nyog yuav tsum paub meej qhov ntsuas kub ntawm qhov chaw hais lus ua haujlwm, thiab txiav txim siab seb cov hlau nplaum twg yuav tsum raug xaiv raws li qhov ntsuas kub. Cov hlau nplaum sib txawv muaj qhov sib txawv ntawm qhov kub thiab txias, thiab qhov siab tshaj plaws ua haujlwm kub lawv tuaj yeem txhawb nqa kuj txawv. Thaum qhov chaw ua haujlwm kub ntawm cov hlau nplaum ntau tshaj qhov ua haujlwm siab tshaj plaws, qhov tshwm sim xws li kev ua haujlwm sib nqus attenuation thiab demagnetization yuav tshwm sim, uas yuav cuam tshuam ncaj qha rau lub suab ntawm tus neeg hais lus.
