【傳聲器(qi)】專業麥(mai)克風的要求 使用傳聲器(qi)的注意事項(xiang)

對專業麥克風的要求

高保真(zhen)和專業(ye)用傳聲器的(de)失(shi)真(zhen)度要小于0.3%，寬頻響范圍，良(liang)好的(de)信噪比性(xing)能，良(liang)好的(de)聲電轉換能力(li)，即(ji)有較高的(de)靈敏度。

傳聲器使用要點

（1）使用傳聲器之前(qian)，應先(xian)了解(jie)傳聲(sheng)器(qi)的類型和特(te)性(xing)，往(wang)往(wang)靜態(tai)(tai)技術指標(biao)稍低而瞬態(tai)(tai)特(te)性(xing)好的傳聲(sheng)器(qi)，要比靜態(tai)(tai)指標(biao)較高而瞬態(tai)(tai)特(te)性(xing)較差的傳聲(sheng)器(qi)更好一些。電容式傳聲(sheng)器(qi)還應注(zhu)意需加供電電源(yuan)。

（2）傳聲(sheng)(sheng)(sheng)器(qi)(qi)位置(zhi)附近不應有大的(de)反射(she)(she)面，如墻(qiang)壁等，以避免強(qiang)烈(lie)的(de)反射(she)(she)聲(sheng)(sheng)(sheng)引起聲(sheng)(sheng)(sheng)音相位干涉而破壞(huai)聲(sheng)(sheng)(sheng)音的(de)自(zi)然度。傳聲(sheng)(sheng)(sheng)器(qi)(qi)與音箱之間的(de)布位也十分重要，一般要求將傳聲(sheng)(sheng)(sheng)器(qi)(qi)安放在(zai)音箱的(de)后面，避開音箱輻(fu)射(she)(she)方向。

（3）傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)的(de)(de)插接(jie)件要牢固(gu)可(ke)靠(kao)。作為傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)插接(jie)件的(de)(de)卡儂或大二(er)芯(xin)插頭、插座(zuo)與(yu)(yu)傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)線焊(han)接(jie)要求很規范。傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)必(bi)須(xu)使用優質屏(ping)蔽(bi)電(dian)纜傳(chuan)送信(xin)號(hao)(hao)(hao)(hao)。由于傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)輸(shu)出信(xin)號(hao)(hao)(hao)(hao)很微弱(ruo)，所以(yi)一(yi)旦竄入干(gan)擾信(xin)號(hao)(hao)(hao)(hao)就(jiu)會(hui)產(chan)生雜音，為此必(bi)須(xu)選(xuan)用金屬(shu)屏(ping)蔽(bi)線傳(chuan)輸(shu)信(xin)號(hao)(hao)(hao)(hao)，并應將(jiang)屏(ping)蔽(bi)線的(de)(de)一(yi)端與(yu)(yu)傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)的(de)(de)外(wai)殼(ke)良(liang)好連(lian)接(jie)，另一(yi)端接(jie)音響(xiang)設備的(de)(de)外(wai)殼(ke)。屏(ping)蔽(bi)線的(de)(de)長度也應盡量短。因為傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)線越長，分布電(dian)容越大，這不(bu)(bu)僅容易(yi)引(yin)起干(gan)擾信(xin)號(hao)(hao)(hao)(hao)，而且會(hui)引(yin)起人(ren)聲(sheng)(sheng)(sheng)(sheng)(sheng)信(xin)號(hao)(hao)(hao)(hao)（特(te)別是高(gao)音）的(de)(de)損耗。一(yi)般(ban)說來(lai)，不(bu)(bu)平(ping)衡連(lian)接(jie)（單芯(xin)屏(ping)蔽(bi)線）時，傳(chuan)聲(sheng)(sheng)(sheng)(sheng)(sheng)器(qi)(qi)連(lian)線的(de)(de)長度不(bu)(bu)宜超過10m，若必(bi)須(xu)加長連(lian)接(jie)線，則(ze)應采用平(ping)衡接(jie)法(fa)（即用雙芯(xin)屏(ping)蔽(bi)線），以(yi)減少(shao)外(wai)來(lai)干(gan)擾。

（4）聲(sheng)(sheng)(sheng)源與傳聲(sheng)(sheng)(sheng)器的距(ju)(ju)離要適當。當演(yan)唱抒情歌曲時，演(yan)員常常將傳聲(sheng)(sheng)(sheng)器靠近嘴邊，以充分利(li)用近講(jiang)效應，提升低(di)音。近講(jiang)傳聲(sheng)(sheng)(sheng)器與嘴部(bu)(bu)的距(ju)(ju)離可在1～20cm。作演(yan)講(jiang)時，為(wei)提高(gao)語言清晰度，傳聲(sheng)(sheng)(sheng)器離嘴部(bu)(bu)宜在20～30cm，甚至還要專門切除(chu)些低(di)頻效果。

（5）由于演(yan)唱或演(yan)講大多使用單(dan)指(zhi)向性(xing)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)，此(ci)時應注意嘴(zui)(zui)(zui)部與(yu)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)中(zhong)心軸(zhou)(zhou)線(xian)(xian)之(zhi)間的(de)(de)夾角大小會(hui)影響拾取聲(sheng)(sheng)(sheng)音(yin)信號(hao)的(de)(de)頻(pin)率特性(xing)。演(yan)唱時，嘴(zui)(zui)(zui)部對準傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)中(zhong)心軸(zhou)(zhou)線(xian)(xian)夾角為0°，傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)輸出的(de)(de)頻(pin)響特性(xing)最佳；嘴(zui)(zui)(zui)部偏離中(zhong)心軸(zhou)(zhou)線(xian)(xian)越遠，頻(pin)率特性(xing)變差，高(gao)音(yin)損失(shi)越嚴重，且傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)輸出電壓也會(hui)減(jian)少。一般心形傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)，嘴(zui)(zui)(zui)部與(yu)中(zhong)心軸(zhou)(zhou)線(xian)(xian)的(de)(de)夾角宜保持(chi)在(zai)45°范圍內，對強指(zhi)向性(xing)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)則應保持(chi)在(zai)30°之(zhi)內。

（6）良好的(de)減(jian)(jian)振(zhen)(zhen)(zhen)裝置。拾音(yin)單元固定在套架(jia)(jia)上(shang)，高檔(dang)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)有減(jian)(jian)振(zhen)(zhen)(zhen)裝置，防止傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)因振(zhen)(zhen)(zhen)動而產生振(zhen)(zhen)(zhen)動噪聲(sheng)(sheng)(sheng)或因傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)意外掉在地(di)上(shang)或因磕碰產生強大的(de)聲(sheng)(sheng)(sheng)沖(chong)擊(ji)，損(sun)壞功放或音(yin)箱的(de)高音(yin)單元。常(chang)用(yong)(yong)的(de)減(jian)(jian)振(zhen)(zhen)(zhen)裝置有橡膠減(jian)(jian)振(zhen)(zhen)(zhen)支架(jia)(jia)、橡膠傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)夾子、橡膠傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)夾子墊、彈簧傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)夾子．使(shi)用(yong)(yong)手持傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)時，不(bu)要握住(zhu)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)網罩，以(yi)免堵塞后面進(jin)氣孔，造成失(shi)真(zhen)，影(ying)響效果。使(shi)用(yong)(yong)無線(xian)傳(chuan)(chuan)聲(sheng)(sheng)(sheng)器(qi)(qi)(qi)時，其載頻(pin)應(ying)避開當地(di)調頻(pin)廣播或無線(xian)電話通信的(de)頻(pin)率，以(yi)免相互串擾(rao)。

（7）抗干擾性(xing)能要(yao)好(hao)(hao)。聲場(chang)中不(bu)可避免地存(cun)在著(zhu)某種(zhong)磁場(chang)和電場(chang)，如(ru)空(kong)調、電源線和人(ren)體的(de)(de)靜電感應等。作為傳聲器(qi)的(de)(de)拾(shi)音(yin)單元(yuan)，很小(xiao)的(de)(de)雜聲干擾經過(guo)調音(yin)臺和功率放(fang)大器(qi)放(fang)大后，送入揚聲器(qi)就(jiu)會形成(cheng)很強(qiang)的(de)(de)雜音(yin)，損害聲音(yin)的(de)(de)質量，所以要(yao)求(qiu)傳聲器(qi)結構、外(wai)殼要(yao)有良好(hao)(hao)的(de)(de)屏蔽作用，要(yao)求(qiu)全金屬結構，防磁性(xing)良好(hao)(hao)，要(yao)用良好(hao)(hao)的(de)(de)屏蔽傳聲器(qi)導線。

（8）在使用(yong)多個(ge)(ge)(ge)傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)進行(xing)拾音(yin)(yin)(yin)時(shi)，首先(xian)應(ying)使各傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)的(de)相(xiang)(xiang)位(wei)一(yi)(yi)致；對一(yi)(yi)個(ge)(ge)(ge)聲(sheng)(sheng)源(yuan)如(ru)需(xu)用(yong)2支(zhi)或(huo)(huo)多個(ge)(ge)(ge)傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)進行(xing)單聲(sheng)(sheng)道拾音(yin)(yin)(yin)（如(ru)會議(yi)拾音(yin)(yin)(yin)）時(shi)就(jiu)將傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)盡量靠近，或(huo)(huo)保持(chi)每個(ge)(ge)(ge)傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)與聲(sheng)(sheng)源(yuan)的(de)距(ju)(ju)離(li)相(xiang)(xiang)等(deng)，以免(mian)相(xiang)(xiang)加時(shi)產(chan)生(sheng)相(xiang)(xiang)位(wei)干涉現象；對2支(zhi)以上聲(sheng)(sheng)源(yuan)如(ru)需(xu)用(yong)2支(zhi)以上傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)拾音(yin)(yin)(yin)時(shi)，應(ying)使每個(ge)(ge)(ge)傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)之間的(de)距(ju)(ju)離(li)大(da)于聲(sheng)(sheng)源(yuan)與傳(chuan)(chuan)聲(sheng)(sheng)器(qi)(qi)間距(ju)(ju)離(li)的(de)3倍(bei)（即滿足3:1規則(ze)），以減(jian)小(xiao)信號相(xiang)(xiang)加時(shi)產(chan)生(sheng)相(xiang)(xiang)位(wei)干涉現象。

（9）要注意(yi)防(fang)(fang)(fang)風、防(fang)(fang)(fang)振、防(fang)(fang)(fang)潮。露(lu)天、室外演出要防(fang)(fang)(fang)風，避免風吹金屬網產(chan)生呼嘯(xiao)聲(sheng)；空氣(qi)中(zhong)的灰塵進入(ru)傳聲(sheng)器，影(ying)響(xiang)磁(ci)隙(xi)的清潔度，會(hui)造(zao)成失(shi)真；近講傳聲(sheng)器，口形與傳聲(sheng)器很近，口中(zhong)的濕(shi)氣(qi)損(sun)害(hai)傳聲(sheng)器的膜片，要使用(yong)防(fang)(fang)(fang)塵防(fang)(fang)(fang)潮罩(zhao)。

傳(chuan)(chuan)聲(sheng)器(qi)(qi)的(de)結構比(bi)較精密(mi)，強烈的(de)振(zhen)動不僅(jin)會使(shi)(shi)傳(chuan)(chuan)聲(sheng)器(qi)(qi)的(de)輸出太大(da)，使(shi)(shi)擴聲(sheng)系統嚴重過載，而且還容易損壞(huai)其(qi)機(ji)械結構，使(shi)(shi)磁(ci)(ci)鐵(tie)退磁(ci)(ci)、降低靈(ling)敏度(du)，使(shi)(shi)音(yin)圈與(yu)磁(ci)(ci)路相碰等，所以要注(zhu)意防振(zhen)。尤(you)其(qi)是(shi)電容傳(chuan)(chuan)聲(sheng)器(qi)(qi)，電容傳(chuan)(chuan)聲(sheng)器(qi)(qi)應先關閉(bi)電源后再移動為好。此外，注(zhu)意不宜用吹氣或用手敲打傳(chuan)(chuan)聲(sheng)器(qi)(qi)的(de)方法來試音(yin)。在(zai)傳(chuan)(chuan)聲(sheng)器(qi)(qi)的(de)保(bao)管中，應注(zhu)意防潮，保(bao)持(chi)清(qing)潔衛生。

（10）傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)的(de)相(xiang)(xiang)位(wei)。如(ru)(ru)果一(yi)部調音(yin)臺同(tong)(tong)(tong)時有(you)多只(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)輸入，若有(you)2支(zhi)(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)相(xiang)(xiang)位(wei)相(xiang)(xiang)反(fan)，當(dang)2支(zhi)(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)信(xin)號(hao)送入調音(yin)臺混合電路中，則信(xin)號(hao)會(hui)(hui)相(xiang)(xiang)互抵消，其聲(sheng)(sheng)(sheng)(sheng)音(yin)反(fan)而會(hui)(hui)減(jian)小，需進行調整。因此(ci)，使(shi)用多個(ge)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)時，尤其是各(ge)種(zhong)不(bu)同(tong)(tong)(tong)型號(hao)的(de)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)同(tong)(tong)(tong)時混合使(shi)用時，傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)的(de)相(xiang)(xiang)位(wei)要一(yi)致。相(xiang)(xiang)位(wei)鑒別可(ke)用下述方(fang)法進行。先(xian)將所用的(de)2支(zhi)(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)放在一(yi)起，同(tong)(tong)(tong)時接收一(yi)個(ge)聲(sheng)(sheng)(sheng)(sheng)源，送出(chu)聲(sheng)(sheng)(sheng)(sheng)響增大，說明2支(zhi)(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)同(tong)(tong)(tong)相(xiang)(xiang)，如(ru)(ru)果送出(chu)聲(sheng)(sheng)(sheng)(sheng)響減(jian)小，并出(chu)現失真，說明傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)反(fan)相(xiang)(xiang)。將其中1支(zhi)(zhi)傳(chuan)(chuan)(chuan)(chuan)聲(sheng)(sheng)(sheng)(sheng)器(qi)(qi)接線調整過來，以達到同(tong)(tong)(tong)相(xiang)(xiang)聲(sheng)(sheng)(sheng)(sheng)。