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英文好的，翻译一下；答题：
Quiz for Music Applications 301
1. The level of the trax that is sent to the monitor speaker is usually independent of the level that is coming from the main speakers.
True False
2. A condenser microphone always has the same output level as a dynamic microphone.
True False
3. The maximum gain-before-feedback is the most amplification of the sound before the sound system goes into feedback and starts squealing.
True False
4. Every time another microphones turns on, the volume before feedback will drop 3 dB.
True False
5. The primary reason to ground your sound system is for safety. A secondary reason to ground is to reduce external noise pickup.
True False
6. Handheld Microphones are usually distinguished by the ball-shaped grille.
True False
7. Mixer channel tone controls are an excellent way to control feedback problems.
True False
8. Handheld microphones usually have their low frequencies intentionally rolled-off.
True False
9. The ensemble or instrument microphone works well at a distance because its bass response has not been rolled-off by the manufacturer.
True False
10. A typical handheld microphone used at a distance from the vocalist will lack bass frequencies.
True False
1. The level of the trax that is sent to the monitor speaker is usually independent of the level that is coming from the main speakers.
True False
2. A condenser microphone always has the same output level as a dynamic microphone.
True False
3. The maximum gain-before-feedback is the most amplification of the sound before the sound system goes into feedback and starts squealing.
True False
4. Every time another microphones turns on, the volume before feedback will drop 3 dB.
True False
5. The primary reason to ground your sound system is for safety. A secondary reason to ground is to reduce external noise pickup.
True False
6. Handheld Microphones are usually distinguished by the ball-shaped grille.
True False
7. Mixer channel tone controls are an excellent way to control feedback problems.
True False
8. Handheld microphones usually have their low frequencies intentionally rolled-off.
True False
9. The ensemble or instrument microphone works well at a distance because its bass response has not been rolled-off by the manufacturer.
True False
10. A typical handheld microphone used at a distance from the vocalist will lack bass frequencies.
True False
多点就好了！哈哈！！
哦，别动摇了您所知道正确的数学与知识，这题我也回答与作者不一样，
结果呢，你可看看它的解释，他是用合唱团3:1迈克风的收音原则来解释，虽然不是那么的让人一看就了解，个人我就顺势把作者想要说明的法则跟各位解释，
如果一支迈克风收一个讯号源有这么大声，离啸叫前还有9 dB，开第二支迈克风收这个同样的音源时，离啸叫前还有6 dB，再开两支来收同样的音源，
那么离啸叫的安全范围只剩3 dB而已，我再打开8支迈克风，但我是去收鼓，并不是与这些迈克风在一起拾取同一音源，而且输入增益与时取时间皆不一样，
那么多了这八支迈克风并不会去影响啸叫的增益范围改变。
其实作者的问题也并没有写出同一音源，所以很利害，让大家脑筋转弯一下也不错的。
结果呢，你可看看它的解释，他是用合唱团3:1迈克风的收音原则来解释，虽然不是那么的让人一看就了解，个人我就顺势把作者想要说明的法则跟各位解释，
如果一支迈克风收一个讯号源有这么大声，离啸叫前还有9 dB，开第二支迈克风收这个同样的音源时，离啸叫前还有6 dB，再开两支来收同样的音源，
那么离啸叫的安全范围只剩3 dB而已，我再打开8支迈克风，但我是去收鼓，并不是与这些迈克风在一起拾取同一音源，而且输入增益与时取时间皆不一样，
那么多了这八支迈克风并不会去影响啸叫的增益范围改变。
其实作者的问题也并没有写出同一音源，所以很利害，让大家脑筋转弯一下也不错的。
答应的事情没忘,鹤,翻译完了
Quiz for Music Applications 301
扩声中的一些问题
1. The level of the trax that is sent to the monitor speaker is usually independent of the level that is coming from the main speakers.
通道送入舞台监听的电平通常独立于主音箱。
You answered Correctly: True
Explanation: A monitor system allows the vocalist to hear the background trax from a speaker that is usually on the floor in front of him (Figure 1). A small personal monitor could also be set on a stand in front of the singer. Or if conditions permit, the monitor could be hung from overhead and aimed back to the singer(s) (Figure 2) . This method works well for the choir. Either way, whoever is singing would be able to hear enough of the background tracks so they would be able to sing their best. Vocalists could probably even have their own voices coming back through the monitors. Many singers find they sing better when they can hear their own voice. Usually, the level of the trax that is sent to the monitor speaker is independent of the level that is coming from the main speakers. That is important, because the sound operator can adjust the track for the right level for the audience, and the singers can hear what they need to hear. There are many different methods to provide a monitor system.
一套监听系统应该允许歌手能够听到在他前方的舞台监听音箱发出的声音.也可以设置一个小型的个人用监听位于歌手的前方(图1).或者如果条件允许,可以将监听音箱悬挂在歌手前上方,并且转过来朝向歌手.这个方法对于合唱比较好(图2).这其中任意一种方法,无论是谁在演唱只要舞台监听能够听的足够清楚,那么歌手也都能够唱出他们的最好水平.歌手甚至应该能够从监听中听到他们自己的声音.很多歌手发现他们在能够听到自己声音的情况下演唱的要好很多.通常,送入舞台监听的音轨电平和送入主音箱的电平是无关的.即更重要的一点,因为音控师可以调节声轨的合适电平给观众和歌手使他们能够听见他们需要去听的.有很多不同的方法提供给监听系统.
2. A condenser microphone always has the same output level as a dynamic microphone.
You answered Correctly: False
Explanation: The choir microphone must be able to pick up voices at 6 to 10 feet away from the microphone. In other words, it must be very sensitive. A condenser microphone can have a 10 to 15 dB higher output level over a dynamic microphone. This means your sound system electronics will not have to provide as much gain or amplification in order to obtain a sufficient volume. The result is a higher signal-to-noise ratio (a lower hiss or noise) and a better dynamic range.
用于拾取合唱的传声器很可能要设置在远离声源6-10步的位置.换句话说,传声器必须有相当的灵敏度.电容传声器能够比动圈传声器多获得10-15dB的输出电平.这就意味着电声音响系统将不用提供更多的增益或者放大器而得到足够的音量.结论就是可以获得更高的信噪比和更好的动态范围.
3. The maximum gain-before-feedback is the most amplification of the sound before the sound system goes into feedback and starts squealing.
You answered Correctly: True
Explanation: Another very important thing to look at is the off-axis frequency response (the response from the sides and the rear of the microphone). The gain-before-feedback and the overall sound is greatly affected by how smooth or even the off-axis response is. Gain-before-feedback is the maximum amplification of the sound before the sound system goes into feedback and starts squealing. The polar graphs of the microphone will give a good idea of its response. Figure 4 shows a microphone which has a very even response. The sound this microphone picks up at the sides is very much like the sound it receives on-axis (the front) except it is lower in volume. The frequency response curve at all angles are nearly the same. It is said to have very little off-axis frequency coloration. Figure 5 shows another type of microphone which has off-axis frequency coloration.
另外一个需要注意观察的重要事情就是脱离轴线的频率反应(这个反应主要来自MIC的侧面和后部).回授临界增益和全部声音响度很大程度上受到传声器脱离轴线部分的频响依然很平滑的影响.回授临界增益是在音响系统将要进入回授和刚开始啸叫时最大化的扩大声音响度.MIC的极面曲线图可以让我们对它的频响有很好的了解.图4显示了一只传声器具有相当平滑的频响.这只传声器拾取它两侧的声音和它拾取位于它轴线(即前方)的声音非常像,除开一些音量上的减弱..它们的频响曲线几乎是相似的.这就是说传声器有着很少的离轴染色效应.图5显示了另一种型号传声器的离轴染色效应.(自己注:这里应该还差几副传声器的频响图,希望知道的朋友告知)
4. Every time another microphones turns on, the volume before feedback will drop 3 dB.
You answered Incorrectly, the correct answer is: False
Explanation: ... If the choir is to be amplified in the room, then gain-before-feedback is always a major concern. Often, the fewer microphones that are used, the greater the chance of success. Every time the number of microphones that are on doubles, the volume before feedback will drop 3 dB. So just adding more microphones will not necessarily mean you will be able to get the choir louder. You must first move the microphones closer to the choir so the sound level reaching the microphones is louder and so the "3 to 1 Rule" is not violated. Of course, you now start picking up more of the individual voices, so the choir members may have to be shifted to provide a better balance. A good Rule of Thumb is to employ one high quality, high output microphone (in other words, a very sensitive microphone) for about 25 people, so a choir of up to 50 would use two microphones. Don't forget - in audio, less is often better.
如果是为合唱扩声,那么回授临界增益总是一个主要的关注点.通常,越少的传声器被使用,就越有接近成功的几率.传声器的数目每增加一倍(而非一只),反馈前音量将损失3dB.所以仅仅增加更多的传声器将不能够使合唱的声音变的更响.首先你必须将传声器移至与合唱队更近以使到达传声器的声压更大,并且不能违反话筒摆位的”3:1”原则.当然,你现在开始拾取到的更多的是单个人的声音,所以合唱成员也许不得不要被轮换来提供一个更好的平衡.一个好的单凭经验来说的办法就是使用一个高品质,高输出传声器(换句话说,一只具有相当灵敏度的传声器)来为25个人拾音,所以如果合唱队有50跟人那就将用2只传声器.千万别忘了在音频中,越少总是越好.
5. The primary reason to ground your sound system is for safety. A secondary reason to ground is to reduce external noise pickup.
You answered Correctly: True
Explanation: Most modern sound equipment has an AC power cord with three terminals on the AC plug. Two of the terminals are for actual AC power. The third round one is the ground terminal (Figure 1). It connects the chassis of the sound equipment to the building's electrical ground. The primary reason we ground a sound system is for safety. A properly grounded sound system will prevent someone from receiving a lethal shock. A secondary reason to ground is to reduce external noise pickup.
大多数现在的音响设备都有一根交流电源线和在交流插座上的三个接线端.两个接线端为了交流电源的有效实际功率.第三根则是地线接线端(图1).它连接了音频设备的底盘和建筑物的地线.第一个原因我们把设备接地是为了安全.一个完全接好地的音像系统将防止有人被电击致命.第二个接地的原因是可以减少外部的噪音被拾取到.
扩声中的一些问题
1. The level of the trax that is sent to the monitor speaker is usually independent of the level that is coming from the main speakers.
通道送入舞台监听的电平通常独立于主音箱。
You answered Correctly: True
Explanation: A monitor system allows the vocalist to hear the background trax from a speaker that is usually on the floor in front of him (Figure 1). A small personal monitor could also be set on a stand in front of the singer. Or if conditions permit, the monitor could be hung from overhead and aimed back to the singer(s) (Figure 2) . This method works well for the choir. Either way, whoever is singing would be able to hear enough of the background tracks so they would be able to sing their best. Vocalists could probably even have their own voices coming back through the monitors. Many singers find they sing better when they can hear their own voice. Usually, the level of the trax that is sent to the monitor speaker is independent of the level that is coming from the main speakers. That is important, because the sound operator can adjust the track for the right level for the audience, and the singers can hear what they need to hear. There are many different methods to provide a monitor system.
一套监听系统应该允许歌手能够听到在他前方的舞台监听音箱发出的声音.也可以设置一个小型的个人用监听位于歌手的前方(图1).或者如果条件允许,可以将监听音箱悬挂在歌手前上方,并且转过来朝向歌手.这个方法对于合唱比较好(图2).这其中任意一种方法,无论是谁在演唱只要舞台监听能够听的足够清楚,那么歌手也都能够唱出他们的最好水平.歌手甚至应该能够从监听中听到他们自己的声音.很多歌手发现他们在能够听到自己声音的情况下演唱的要好很多.通常,送入舞台监听的音轨电平和送入主音箱的电平是无关的.即更重要的一点,因为音控师可以调节声轨的合适电平给观众和歌手使他们能够听见他们需要去听的.有很多不同的方法提供给监听系统.
2. A condenser microphone always has the same output level as a dynamic microphone.
You answered Correctly: False
Explanation: The choir microphone must be able to pick up voices at 6 to 10 feet away from the microphone. In other words, it must be very sensitive. A condenser microphone can have a 10 to 15 dB higher output level over a dynamic microphone. This means your sound system electronics will not have to provide as much gain or amplification in order to obtain a sufficient volume. The result is a higher signal-to-noise ratio (a lower hiss or noise) and a better dynamic range.
用于拾取合唱的传声器很可能要设置在远离声源6-10步的位置.换句话说,传声器必须有相当的灵敏度.电容传声器能够比动圈传声器多获得10-15dB的输出电平.这就意味着电声音响系统将不用提供更多的增益或者放大器而得到足够的音量.结论就是可以获得更高的信噪比和更好的动态范围.
3. The maximum gain-before-feedback is the most amplification of the sound before the sound system goes into feedback and starts squealing.
You answered Correctly: True
Explanation: Another very important thing to look at is the off-axis frequency response (the response from the sides and the rear of the microphone). The gain-before-feedback and the overall sound is greatly affected by how smooth or even the off-axis response is. Gain-before-feedback is the maximum amplification of the sound before the sound system goes into feedback and starts squealing. The polar graphs of the microphone will give a good idea of its response. Figure 4 shows a microphone which has a very even response. The sound this microphone picks up at the sides is very much like the sound it receives on-axis (the front) except it is lower in volume. The frequency response curve at all angles are nearly the same. It is said to have very little off-axis frequency coloration. Figure 5 shows another type of microphone which has off-axis frequency coloration.
另外一个需要注意观察的重要事情就是脱离轴线的频率反应(这个反应主要来自MIC的侧面和后部).回授临界增益和全部声音响度很大程度上受到传声器脱离轴线部分的频响依然很平滑的影响.回授临界增益是在音响系统将要进入回授和刚开始啸叫时最大化的扩大声音响度.MIC的极面曲线图可以让我们对它的频响有很好的了解.图4显示了一只传声器具有相当平滑的频响.这只传声器拾取它两侧的声音和它拾取位于它轴线(即前方)的声音非常像,除开一些音量上的减弱..它们的频响曲线几乎是相似的.这就是说传声器有着很少的离轴染色效应.图5显示了另一种型号传声器的离轴染色效应.(自己注:这里应该还差几副传声器的频响图,希望知道的朋友告知)
4. Every time another microphones turns on, the volume before feedback will drop 3 dB.
You answered Incorrectly, the correct answer is: False
Explanation: ... If the choir is to be amplified in the room, then gain-before-feedback is always a major concern. Often, the fewer microphones that are used, the greater the chance of success. Every time the number of microphones that are on doubles, the volume before feedback will drop 3 dB. So just adding more microphones will not necessarily mean you will be able to get the choir louder. You must first move the microphones closer to the choir so the sound level reaching the microphones is louder and so the "3 to 1 Rule" is not violated. Of course, you now start picking up more of the individual voices, so the choir members may have to be shifted to provide a better balance. A good Rule of Thumb is to employ one high quality, high output microphone (in other words, a very sensitive microphone) for about 25 people, so a choir of up to 50 would use two microphones. Don't forget - in audio, less is often better.
如果是为合唱扩声,那么回授临界增益总是一个主要的关注点.通常,越少的传声器被使用,就越有接近成功的几率.传声器的数目每增加一倍(而非一只),反馈前音量将损失3dB.所以仅仅增加更多的传声器将不能够使合唱的声音变的更响.首先你必须将传声器移至与合唱队更近以使到达传声器的声压更大,并且不能违反话筒摆位的”3:1”原则.当然,你现在开始拾取到的更多的是单个人的声音,所以合唱成员也许不得不要被轮换来提供一个更好的平衡.一个好的单凭经验来说的办法就是使用一个高品质,高输出传声器(换句话说,一只具有相当灵敏度的传声器)来为25个人拾音,所以如果合唱队有50跟人那就将用2只传声器.千万别忘了在音频中,越少总是越好.
5. The primary reason to ground your sound system is for safety. A secondary reason to ground is to reduce external noise pickup.
You answered Correctly: True
Explanation: Most modern sound equipment has an AC power cord with three terminals on the AC plug. Two of the terminals are for actual AC power. The third round one is the ground terminal (Figure 1). It connects the chassis of the sound equipment to the building's electrical ground. The primary reason we ground a sound system is for safety. A properly grounded sound system will prevent someone from receiving a lethal shock. A secondary reason to ground is to reduce external noise pickup.
大多数现在的音响设备都有一根交流电源线和在交流插座上的三个接线端.两个接线端为了交流电源的有效实际功率.第三根则是地线接线端(图1).它连接了音频设备的底盘和建筑物的地线.第一个原因我们把设备接地是为了安全.一个完全接好地的音像系统将防止有人被电击致命.第二个接地的原因是可以减少外部的噪音被拾取到.
6. Handheld Microphones are usually distinguished by the ball-shaped grille.
You answered Correctly: True
Explanation: Close-Proximity Microphones (handheld) are usually distinguished by the ball-shaped grille (see Figure 1). They are designed with low-frequency roll-off to compensate for proximity effect. When most directional microphones are used within 12" of the sound source, the bass is louder.
非常靠近(声源)的传声器(手持式)通常是球形铁格子状.(见图1).它们被设计成低频滚降式的来补偿低频近讲效应.当大多数指向性传声器被用于离声源12"内时,低频会更加响.
7. Mixer channel tone controls are an excellent way to control feedback problems.
You answered Correctly: False
Explanation: And don't assume that the channel tone controls on your mixer will do the job. First of all, channel tone controls should not be used to control feedback problems. And second, the tonal quality problems associated with lavalier microphones are usually difficult to fix with the type of tone controls found on most sound mixers.
不要假想你的调音台上通道的均衡可以作这项工作.首先,通道均衡就不是被设计拿来解决回授问题的.第二点,结合传声器的音质问题通常很难融入进这种设置的均衡器所基于的大多数调音台.
8. Handheld microphones usually have their low frequencies intentionally rolled-off.
You answered Correctly: True
Explanation: Another important thing to look for in a choir microphone is a flat frequency response. This means the microphone should pick up all the audio frequencies at the same volume. Many microphones have their low frequencies intentionally rolled-off (less sensitive). A typical example is shown in Figure 1. It is designed to be used close to the mouth. Notice in Figure 1 how the bass is rolled off starting at about 250 Hz. That frequency is about the first "A" below "middle C." The fundamental frequencies of male voices are below this frequency. When this microphone is used at a distance, it will sound quite thin or tinny because of the low bass pick-up. However, when it is used as designed (within 6 inches) it will sound much better due to the bass boost which is caused by the proximity effect (Figure 2).
另外一个重要的事情对于寻找一只用于合唱用的传声器就是要有平坦的频率响应.这就意味着这个传声器应该能够以同等的音量拾取到各个声音的频段.很多传声器都有它们自己的低频都有着滚降(较小的灵敏度).一个典型的例子请看图1.它就是被设计成用于可以很靠近嘴巴的.注意图1中低频部分在250Hz处是如何开始滚降的.那个频率处于钢琴的的终殃C和标准音440Hz之间.(这句相当拿不准).男声发声频率的基频是低于这个频率的.当这只传声器被用在与声源处于一段距离时,它拾取的声音将非常单薄因为低频被消减.无论如何,当传声器被设计成这样使用时(6英寸内),它所拾取的声音会更好,因为由于低频近讲效应所造成的低频部分提升被衰减了.
9. The ensemble or instrument microphone works well at a distance because its bass response has not been rolled-off by the manufacturer.
You answered Incorrectly, the correct answer is: True
Explanation: Why is it important to know what type of microphone to select? If you use a Close-Proximity microphone 3 or 4 feet from the vocalist, the sound will lack bass frequencies. The ensemble or instrument microphone will sound much better at a distance, because its bass response has not been rolled-off by the manufacturer.
为什么要知道选用何种传声器是重要的呢?如果你用一只低频衰减了的传声器距离歌手3到4步远,拾取的声音将会缺少低频成分.用于合唱或者乐器的传声器将设置离声源一定距离这样会更好听些,因为它们的低频部分没有被制造厂商做低频滚降处理.
10. A typical handheld microphone used at a distance from the vocalist will lack bass frequencies.
You answered Correctly: True
Explanation: Why is it important to know what type of microphone to select? If you use a Close-Proximity microphone 3 or 4 feet from the vocalist, the sound will lack bass frequencies. The ensemble microphone will sound much better at a distance, because its bass response has not been rolled-off by the manufacturer.
为什么要知道选用何种传声器是重要的呢?如果你用一只低频衰减了的传声器距离歌手3到4步远,拾取的声音将会缺少低频成分.用于合唱或者乐器的传声器将设置离声源一定距离这样会更好听些,因为它们的低频部分没有被制造厂商做低频滚降处理.
最后注:最后两点的解释是一样的.原文中提到了许多图片,但是没能找到,知道的朋友可以发上来,才疏学浅,翻译中有不足之处请指出,谢谢.
You answered Correctly: True
Explanation: Close-Proximity Microphones (handheld) are usually distinguished by the ball-shaped grille (see Figure 1). They are designed with low-frequency roll-off to compensate for proximity effect. When most directional microphones are used within 12" of the sound source, the bass is louder.
非常靠近(声源)的传声器(手持式)通常是球形铁格子状.(见图1).它们被设计成低频滚降式的来补偿低频近讲效应.当大多数指向性传声器被用于离声源12"内时,低频会更加响.
7. Mixer channel tone controls are an excellent way to control feedback problems.
You answered Correctly: False
Explanation: And don't assume that the channel tone controls on your mixer will do the job. First of all, channel tone controls should not be used to control feedback problems. And second, the tonal quality problems associated with lavalier microphones are usually difficult to fix with the type of tone controls found on most sound mixers.
不要假想你的调音台上通道的均衡可以作这项工作.首先,通道均衡就不是被设计拿来解决回授问题的.第二点,结合传声器的音质问题通常很难融入进这种设置的均衡器所基于的大多数调音台.
8. Handheld microphones usually have their low frequencies intentionally rolled-off.
You answered Correctly: True
Explanation: Another important thing to look for in a choir microphone is a flat frequency response. This means the microphone should pick up all the audio frequencies at the same volume. Many microphones have their low frequencies intentionally rolled-off (less sensitive). A typical example is shown in Figure 1. It is designed to be used close to the mouth. Notice in Figure 1 how the bass is rolled off starting at about 250 Hz. That frequency is about the first "A" below "middle C." The fundamental frequencies of male voices are below this frequency. When this microphone is used at a distance, it will sound quite thin or tinny because of the low bass pick-up. However, when it is used as designed (within 6 inches) it will sound much better due to the bass boost which is caused by the proximity effect (Figure 2).
另外一个重要的事情对于寻找一只用于合唱用的传声器就是要有平坦的频率响应.这就意味着这个传声器应该能够以同等的音量拾取到各个声音的频段.很多传声器都有它们自己的低频都有着滚降(较小的灵敏度).一个典型的例子请看图1.它就是被设计成用于可以很靠近嘴巴的.注意图1中低频部分在250Hz处是如何开始滚降的.那个频率处于钢琴的的终殃C和标准音440Hz之间.(这句相当拿不准).男声发声频率的基频是低于这个频率的.当这只传声器被用在与声源处于一段距离时,它拾取的声音将非常单薄因为低频被消减.无论如何,当传声器被设计成这样使用时(6英寸内),它所拾取的声音会更好,因为由于低频近讲效应所造成的低频部分提升被衰减了.
9. The ensemble or instrument microphone works well at a distance because its bass response has not been rolled-off by the manufacturer.
You answered Incorrectly, the correct answer is: True
Explanation: Why is it important to know what type of microphone to select? If you use a Close-Proximity microphone 3 or 4 feet from the vocalist, the sound will lack bass frequencies. The ensemble or instrument microphone will sound much better at a distance, because its bass response has not been rolled-off by the manufacturer.
为什么要知道选用何种传声器是重要的呢?如果你用一只低频衰减了的传声器距离歌手3到4步远,拾取的声音将会缺少低频成分.用于合唱或者乐器的传声器将设置离声源一定距离这样会更好听些,因为它们的低频部分没有被制造厂商做低频滚降处理.
10. A typical handheld microphone used at a distance from the vocalist will lack bass frequencies.
You answered Correctly: True
Explanation: Why is it important to know what type of microphone to select? If you use a Close-Proximity microphone 3 or 4 feet from the vocalist, the sound will lack bass frequencies. The ensemble microphone will sound much better at a distance, because its bass response has not been rolled-off by the manufacturer.
为什么要知道选用何种传声器是重要的呢?如果你用一只低频衰减了的传声器距离歌手3到4步远,拾取的声音将会缺少低频成分.用于合唱或者乐器的传声器将设置离声源一定距离这样会更好听些,因为它们的低频部分没有被制造厂商做低频滚降处理.
最后注:最后两点的解释是一样的.原文中提到了许多图片,但是没能找到,知道的朋友可以发上来,才疏学浅,翻译中有不足之处请指出,谢谢.