考考你对动态细节知道多少

作者：Rick Kreifeldt，Harman Proessional SDIG（哈曼国际集团系统研发与集成部）副总裁

每个问题仅有一个答案：祝你好运!

1.) What does a Compression Ratio of 4:1 mean?
 4：1的压缩比是什么意思？

A.) Once past the threshold, the input signal must increase by 4dB for the output to increase by one dB.
      一旦超过阈值，输出信号增加1dB，输入信号必须增加4dB
B.) Once past the threshold, the output signal will be 4dB less than the input signal.
      一旦超过阈值，输出信号会比输入信号减少4dB
C.) Once past the threshold, the compressor will have 4dB of gain reduction.
      一旦超过阈值，压缩器会有4dB的增益衰减



2.) Compressor attack time is defined as:
 压缩器的启动时间的意思是：

A.) The time it takes for the compressor to come out of gain reduction.
     压缩器结束增益衰减所需要的时间
B.) The time it takes before the compressor starts gain reduction.
     压缩器开始增益衰减之前所需要的时间
C.) The time it takes for the compressor to enter full gain reduction.
     压缩器达到满增益衰减所需要的时间
D.) None of the above.
     以上都不是



3.) Signals below the compressor threshold pass through without being compressed:
 处于压缩器阈值下的信号不会被压缩，直接通过

A.) True
     对
B.) False
     错



4.) If a compressor is showing 10dB of gain reduction and you add 10dB of makeup gain,
lower level signals below the threshold will be: 
如果压缩器显示10dB的增益衰减，而你增加了10dB的弥补增益，阈值下方的较低电平信号会：

A.) Reduced by 10dB.
     衰减10dB
B.) 10dB louder.
     增加10dB
C.) 20dB louder.
     增加20dB



5.) Signals below the threshold of a downward expander are:
 低于下限拓展器阈值的信号会：

A.) Passed through without any gain reduction.
     不经过任何增益衰减直接通过
B.) Reduced by the downward expander ratio.
     下限拓展器对其按比率进行衰减
C.) Made louder by the expansion ratio.
     拓展比使其更响



6.) A soft knee compressor:
 软拐点压缩器：

A.) Starts compression before the threshold.
     在达到阈值前就开始压缩
B.) The compressor will not be at the full compression ratio until after the threshold.
     在信号达到阈值之前，压缩器不会达到满压缩比
C.) Has a lower output level at the threshold than a hard knee compressor.
     在阈值电平的输出电平比硬拐点低 
D.) All of the above
     以上所有



7.) Gate attack time is defined as:
 噪声门的启动时间是

A.) The time it takes for the gate to enter gain reduction.
      噪声门进入增益衰减所需的时间
B.) The time it takes for the gate to close.
      噪声门关闭所需的时间
C.) The time it takes for the gate to come out of gain reduction.
      噪声门离开增益衰减所需的时间
D.) None of the above..
      以上都不是



8.) A parametric EQ with a bandwidth of 1/4 octave inserted into the side chain of a compressor
with a boost of 6dB at 1 kHz will cause the compressor to compress a signal at 1kHz more than a signal at 100 Hz. 
带宽为1/4倍频程的参量均衡器插入到一台压缩器的旁链中，在1kHz提升6dB会使压缩器对1kHz的压缩比100Hz的信号更多。

A.) True
     对
B.) False
     错



9.) An optical compressor uses what for the gain element:
 光学压缩器的增益元件用的是什么材料

A.) Photo cell and LED.
     光电池和LED
B.) Photo diode and LED.
     光二极体和LED
C.) Fiber optic VCA.
     光纤压控放大器
D.) Flux Capacitor.
     通量电容器



10.) A compressor is set to a 3:1 ratio. The threshold is set at +3dBu.
If the input signal is at +12dBu, what is the level of the output signal?
压缩器设为3：1的压缩比。阈值设在+3dBu。如果输入信号在+12dBu。输出信号的电平是多少？

A.) +4dBu.
B.) +5dBu.
C.) +6dBu.
D.) +7dBu.



11.) A gate has a look-ahead time of 600uSec. Which of the following is true:
 噪声门有600微秒的前瞻时间。下面哪项是正确的：

A.) The gate will open 600uSec faster if this feature is turned on.
     如果打开，噪声门会比平时快600微秒打开。 
B.) The gate looks 600uSec ahead in time to see if it will need to open.
     如果打开，噪声门会实时监视后面600微秒的信号
C.) The gate will open in 600uSec plus the attack time.
     噪声门会在600微秒的时间内打开，这其中包含启动时间
D.) The main signal will be delayed by 600uSec so that the gate will have time to open before the signal passes through the gain element.
     主信号会被延时600微秒，这样噪声门就有时间在信号通过增益元件前打开。



12.) What will be the result of running the kick drum into the key input of the bassist’s gate? 
 当底鼓的信号进入到贝司手的噪声门旁链插入端后会怎样？

A.) When the kick drum is played, the bassist’s sound will be compressed.
     当敲响底鼓时，贝斯的声音会被压缩
B.) The bass will only be heard when the kick is played.
     只有在敲底鼓时贝斯才能被听到
C.) The bassist will finally be in time.
     贝斯手最后会与鼓手同步
D.) The drummer will finally be on time.
     鼓手最后会准时演奏



13.) An acoustic guitar player switches between strumming and finger picking in the same song.
Which of the following compressor settings will make his finger picking 8 dB louder if his strumming peaks at 8dBu?
一名吉他手在同一首歌中分别使用扫弦和指弹两种方法演奏。如果扫弦时峰值在8dBu，下面哪种压缩器设定能让指弹电平也增加8dB。

A.) Adjust the threshold to 8dBu and the ratio to 2:1.
     调整门限到8dBu，压缩比为2：1
B.) Adjust the threshold to 0dBu with a ratio of Infinity:1.
     调整门限到0dBu，压缩比为无限：1 
C.) Adjust the threshold and ratio until you have 8dB on the gain reduction meter when he is strumming and
     no gain reduction when he is finger picking. Add 8dB of make-up gain.
     当扫弦时，调整门限和压缩比直到指示表中显示8dB的增益衰减，而在指弹时没有任何增益衰减。增加8dB的弥补增益。
D.) Adjust the threshold 0dBu and the ratio to 8:1; add 8dB of make-up gain.
     调整门限电平为0dBu，压缩比为8：1，增加8dB的弥补增益。



14.) You are using a digital limiter. The A/D of the digital compressor reaches it’s maximum output
when the input signal is at +22dBu, and the box is unity gain.
你使用的是数字限制器。当输入信号在+22dBu时，数字压缩器的A/D达到最大输出，机器是单位增益。

Assuming no other gain through the unit, at what threshold must you set the digital limiter
so that the output signal will not exceed +10dBu? 
不调整这台机器中的其它增益功能，如果想让输出电平不超过+10dBu，你该怎样设置数字限制器的门限。

A.) -12dBFS
B.) +10dBFS
C.) +12dBFS
D.) -10dBFS



15.) If a downward expander is set at a ratio of 1:1.5, a threshold of 40dBu, and a maximum attenuation or depth of 20dB,
how much gain reduction will there be if the input signal is at 50dBu?
如果下限拓展器的比率设为1：1.5，门限为-40dBu，最大衰减或深度为20dB，如果输入信号在-50dBu，增益会衰减多少?

A.) 10
B.) 12.5
C.) 15
D.) 20



16.) Compression ratio of 2:1. Compressor threshold of 10dBu. Limiter threshold of 0dBu.
If the input signal is at +10dBu, how much gain reduction is being contributed by the limiter:
压缩比为2：1，压缩器阈值为-10dBu。限制器阈值为0dBu。如果输入信号在+10dBu，限制器会贡献多少增益衰减？

A.) 10dB
B.) 5dB
C.) 20dB
D.) None
E.) 15dB



17.) If you want to duck music when someone talks into a mic, you should:
 有人对着麦克讲话时，你想减小音乐音量，你应该：

A.) Use a gate with the music going through the gate and the mic plugged into the key input.
     使用噪声门，音乐经过噪声门，麦克接到旁链输入。
B.) Use a mixer to add the two signals, and then use mixed signal into a key input of a gate.
     使用混音器混合这两个信号，然后混合信号送入噪声门的旁链输入。
C.) Use a compressor, with the music going though the compressor and the mic plugged into the side chain insert.
     使用压缩器，音乐经过压缩器，麦克风接到旁链插入。
D.) None of the above.
      以上都不是



18.) A Hi-Shelf EQ is inserted into the side chain of a compressor. The EQ is set to cut 10dB at 5kHz with a slope of 18 dB/octave.
The compressor is set to 2:1 at a threshold of -10dBu. If the input signal is +10dBu at a frequency of 10kHz, what is the level of
the output signal?
一个高频搁架式EQ插入到压缩器的旁路中。EQ设为在5kHz衰减10dB，斜率为18dB/倍频程。压缩器的门限设为-10dBu，压缩比设为2：1，
如果输入信号是+10dBu的10kHz信号。输出电平将是多少？

A.) -5dBu
B.) 0dBu
C.) +5dBu
D.) +10dBu



19.) Which compressor settings will most accentuate the transient attack of a snare drum?
 哪一种压缩器设定最能突出小军鼓的瞬态？

A.) Fast attack and slower release.
     快启动和慢释放
B.) Fast release and slower attack.
     快释放和慢启动
C.) Fast attack, fast release, long hold time.
     快启动，快释放，长保持时间
D.) -15dB
E.) Slow attack, slow release, short hold time.
     慢启动，慢释放，短保持时间。



20.) Assuming you have a unit which is a multi-band compressor / limiter, which of the following statements is NOT true:
 假设你有一台多频段压缩/限制器，下面哪项表述不正确

A.) A multi-way crossover is used to divide up the frequency bands.
     多路分频器用于分配频段
B.) This unit can be used to de-ess full program material.
     这台机器可以对整体节目素材去丝声
C.) For each band you have a separate VCA and RMS detector.
     每频段都有独立的VCA和RMS检波器
D.) Setting the threshold of each band’s limiter to 0dBu will ensure that the output will not be above 0dBu.

     将每段限制器的阈值设为0dBu会保证输出不会超过0dBu