Narrator: Listen to part of a lecture in an architecture class.

旁白：听一段建筑学的演讲。

Professor: Today I'd like to talk a bit about the relationship between the built world and sound.

教授：今天我谈谈建筑世界和声音之间的关系。

Uh, the design of buildings like concert halls or theaters.

额，像是音乐厅或者剧院这种建筑设计。

So, what's the most important aspect in the design of such a building?

那么，对于这种建筑的设计，最重要的一方面是什么呢？

Student: Acoustics?

学生：音响效果？

Professor: Yes. Now, people have been concerned about how sound carries in auditoriums and theaters for at least 2,000 years.

教授：是的。人们关注听众席和剧院中声音是如何被传播的已经有2000年的时间了。

But it was not until the beginning of the twentieth century that architectural acoustics became a scientific field.

但是直到20世纪初，建筑声学才成为了一个科学领域。

That was when the physicist Wallace Sabine started to do extensive studies on reverberation.

在那个时候物理学家Wallace Sabine开始对混响做大量的研究。

Sabine wanted to find out why the audience could not understand speakers at a lecture hall in Boston.

Sabine想弄清楚为什么在一个波士顿演讲厅中，观众不能听清演讲者的话。

He designed a series of studies on reverberation to figure it out.

他设计了一系列的混响研究去查明原因。

So, what is reverberation?

那么，什么是混响？

It's the persistence of sound in a room after the source has stopped making sound.

它指的是当声源已经停止发声，声音还在房间中持续着。

You see, sound made in a room reflects off the walls, floors and ceiling.

你知道的，在房间中制造出的声音从墙面、地面以及天花板上反射出来。

That's the reverberant sound.

这就是回响的声音。

The time it takes for the reverberant sound to die down is important for the acoustic quality of a room.

回响声音逐渐平息的时间长短对于一个房间音质是很重要的。

Sabine recognized this and he came up with an equation to measure a room's reverberation time.

Sabine意识到了这一点，并且他想出了一个方程式去测试一个房间的混响时间。

So, what happens if the reverberation time is very long?

那么，如果混响时间太长了，会怎么样？

Student: Wouldn't it be difficult to hear new sounds if you can still hear the old sounds?

学生：如果你还听得到原来的声音，要听清新的声音会不会很困难？

Professor: Exactly. A long reverberation time may cause musical notes to drown one another out.

教授：正是如此。一个长的混响时间会是一个音符将另一个音符淹没。

On the other hand, if the reverberation time is very short…meaning, the reverberations are absorbed very quickly, the room is called dead.

另一方面，如果混响时间太短，意思是，混响被吸收的很快，这个房间就被称为无生命的。

Performers would feel they have to struggle to fill the room with sound.

表演者会觉得他们必须要奋力将屋子填满声音。

We don't want that.

我们并不希望那样。

In a concert hall or theater, we prefer a live room, where the sound has fullness.

在一个音乐厅或者剧院中，我更喜欢一个混响室，在那里声音是丰富的。

So we need to control the reverberation time.

所以，我们必须控制混响时间。

After all, we don't want the listeners or the performers to have to struggle, right?

毕竟，我们不希望听众或者表演者去挣扎，是不是？

So what are some important considerations when we design a theater or a concert hall?

那么，当我们设计一个剧院或者音乐厅时，什么是重要的考量？

Student: The size of the place?

学生：这个地方的大小？

Professor: Absolutely. The larger the room, the longer the reverberation time.

教授：绝对的。房间越大，混响时间就越长。

So we'll have to take into account what the room will be mainly used for, since music requires more reverberation than speech.

所以，我们必须考虑这个房间主要是用来干什么的，因为音乐比演讲需要更多的混响。

A room intended for music needs to be designed differently from a room intended for drama.

为音乐设计的房间和为戏剧设计的房间是不同的。

For music, we need a very large room, a concert hall, actually I should say for full orchestras.

对于音乐，我们需要一个大的房间，一个音乐厅，事实上我应该说是给整个管弦乐队。

Because for a single instrument, say something like a piano recital, a room with a short reverberation time is better.

因为对于单个乐器来说，比如钢琴独奏会，一个有着短混响的房间会更好。

So for a solo piano a smaller room works well. Yes?

所以，对于钢琴独奏，小一点的房间会更好。有什么问题吗？

Student: I read that concert halls designed for symphony orchestras have too much echo for jazz music.

学生：我读到过为交响乐团设计的音乐厅对于爵士乐来说，回声太多。

Professor: That doesn't surprise me.

教授：那个我并不惊讶。

Most small jazz groups would need rooms with a shorter reverberation time.

大部分小的爵士乐团需要一个较短混响的房间。

But besides the size of the room, another variable affecting reverberation is the shape of the room.

但是除了房间的大小，另一个影响混响的因素就是房间的形状。

Let's say you design a rectangular box-like space with bare walls and ceiling, this would allow the sound to act like a ball in a racquetball court, you know, bouncing around and hitting some parts of the walls and ceiling but missing many others.

假如你用光的墙壁和天花板为一个长方形盒装的空间作设计，这个会使声音听上去像是壁球场里的球一样，你知道的，会弹来弹去，击中部分的墙面和天花板，但是也会错过一些墙面。

If that happens in a concert hall, audience members may hear some sounds, but not others.

如果发生在一个音乐厅里，听众们可能会听到部分的声音，而其他的却听不到。

So what can be done to distribute the sound evenly in every direction?

所以，要怎么来平均地将声音分散到各个方向呢？

The answer is: avoid straight, parallel walls. Karen?

答案就是：避免直线的，平行的墙面。Karen?

Student: But I think I've seen photos of rectangular concert halls.

学生：但是我想我看到过长方形音乐厅的照片。

Professor: Right. Older concert halls from the 1800s are generally rectangular.

教授：是的，在19世纪的老音乐厅大多是长方形的。

But they all have a lot of decorations on the walls inside, lots of ornamental plasterwork like statues, which distribute sound very efficiently, reflecting it in all different directions.

但是他们在室内墙壁上有很多的装饰品，很多石膏装饰如雕像，这些装饰品可以很有效地传递声音，并从不同的方向反射声音。

And that brings me to another variable we need to consider.

这个就牵涉到我们要考虑的另一个变量了。

The acoustic characteristics of the building materials as well as the wall and floor coverings.

建筑以及墙壁地板覆盖物的材料。

In fact, most objects you see in a concert hall or theater serve double duty.

事实上，大部分你在音乐厅或者剧院看到的东西都有双重功能。

The plush chairs absorb sound and soften reverberation.

长绒座椅吸收声音并且会柔化混响。

And the beautiful crystal Chandeliers?

那么漂亮的水晶吊灯呢？

They are very good at diffusing sound.

它们可以非常好地扩散声音。

You see, everything must be planned down to the last detail in order to predict the acoustic performance of a room.

为了要预测一个房间的声效，每个事物都必须要策划到最后一个细节。

That being said, there's something that can’t be controlled by the architect.

有这样一个说法，有些事情是不受建筑师的控制的。

The audience has an effect on acoustics too.

观众对声效也有影响。

The heads of people are good diffusers of sound.

人们的脑袋也是声音很好的扩散器。

And Architects try to account for this effect in their design, but they can't guarantee a full auditorium.

建筑师尝试将这个纳入设计的考量，但是他们并不能保证一定满座。