Envelope
包络/Bao1 Luo4
n/a
CHEARS: False
EARS: True
CMT: True
EARS2 Encyclopedia: True
CHEARS:
EARS: Machine Translation / MySQL (beta) at CHEARSdotinfo.co.uk
EARS:
The profile of the evolution of the intensity and/or spectrum of a sound during its duration. Other uses of the term concern frequency and filter evolution in time, primarily on synthesizers.
EARS2:
The shape of a sound over time. It can be described by using the terms ADSR (Attack, Decay, Sustain, Release).
Envelope The profile of the evolution of the intensity and/or spectrum of a sound during its duration. [EARS] Those who use synthesizers or software-based systems will be acquainted with the terms that are often related to an envelope's design: attack, decay, sustain, release or ADSR.
EARS 2: MT / MySQL (beta) at CHEARSdotinfo.co.uk
声音的生命
每个声音都有音头，音腹和音尾。所有的声音都随着时间而变化。
声音不同则包络不同。包络的形态可以影响我们的声音听感。
创作技巧
包络形态将会影响声音的听感。
分解包络
为了帮助我们讨论声音的包络，我们需要将其分解成为四个清晰的部分。
起冲 – 声音的起始速度。
衰减 – 从起冲跌落到平稳状态的时间。
延留 – 声音生命周期中的一个稳定时期。
消去 – 逐渐衰减到无声。
每个声音都将天生的拥有这些部分，但分配比例不同（有些声音将只会拥其中有两到三个部分。）
起冲
起冲有时会很短，有时也会很长。起冲是大脑用来尝试识别声音的重要组成部分之一。
快起冲
这个声音拥有一个快起冲。聆听它的起始（时间）有多快。
慢起冲
这个声音拥有一个慢起冲。你可以听到它是如何慢慢显现的。它的声音非常柔和并且平稳。
快起冲的声音是比较清脆的，而慢起冲则会显的更平稳和圆润。
延留
声音发出了一个长延留（时间）的响声。
长延留
这个声音拥有一个长延留（时间），聆听其平稳的音色。
如果我们消减了延留部分，那我们就会把注意力放在起冲上。
短（或无）延留
延留声音此时不发声了，声音从音头几乎瞬间淡出。
拥有长延留的声音将会持续发声很长时间。拥有短延留的声音将会非常短促 。
聆听范例：钟铃
如果我们聆听钟铃的声音，我们可以听到它回荡着的长延留声。
原始钟铃
这个钟铃声拥有一个长延留（时间），不断的响了很久，随着它的震动慢慢消亡。
但是如果我们用布按住同样的钟铃并抑制其发声，我们就会去掉所有的延留，并主要保留它的起冲。
被抑制的钟铃
这次，布阻止了钟铃的震动和发声。它几乎立刻抑制了延留声。
通过布来抑制震动，我们改变了钟铃的包络，从而突出了声音的起冲。
关于其他部分的包络附加信息
包络的其他两个部分 – 衰减和消去 – 同样在声音呈现方式中扮演者重要角色，但它们却更加微妙。
衰减
消去
声音最终会淡出。我们在聆听声音时，常常会顾头不顾尾。
无论如何，“消去”部分会让我们所听到的声音变得不同。
短消去
这个声音结束的非常突然。好像被某个人狠踩了急刹车。
长消去
这个声音在平稳的消去（时间）中渐渐淡出。
一个拥有长消去（时间）的声音最终会很长，并会慢慢淡出。而拥有短消去的声音则会快速淡出。
包络的变形
由于包络是声音的一个非常重要的属性，改变并且变形声音的包络，会大大影响声音的最终听感。
反转
当我们反转声音时，我们也反转了包络。因此起冲变成了消去，而消去变成了起冲。
原始声音
聆听原始声音的包络。它有一个快起冲（时间），紧接一个慢衰减（时间） – 延留（时间） – 消去（时间）。
被反转的包络
这个声音被反转了，因此包络现在也逆向了。对比原始的声音，我们现在有了一个慢起冲（时间），紧接着一个快衰减（时间） – 消去（时间）（这里竟然已经没有延留部分了）。
反转声音的手段经常被用于各种不同的音乐风格中。反转包络会让声音变得非常不同，并且创造非常梦幻的新声音。
拼贴
拼贴声音允许我们去除或者重新组织声音包络的各个部分。通过去掉包络的其中一个部分，我们可以戏剧性的转变声音的听感。
原始声音
这个声音有一个清晰的强起冲。 你可以听到“敲击”玻璃的声音。
由于起冲是我们大脑识别声音来源的重要信息之一，通过去除起冲，我们可以隐藏声音的来源。
通过拼贴去除起冲
这个声音曾经的起冲部分通过拼贴手段被去掉了。我们不再会听到玻璃的敲击声，仅能听到玻璃的延留声。
去除（或变形）声音包络的起冲部分，可以帮助我们隐藏原始声音的来源，同时可以让听者将注意力集中在声音的不同方面。
附加
声音包络的形态直接关系到物体的震动和发声。声音的属性以及促进其发声的方式，都将会影响包络的最终属性。
例如：思考拨奏琴弦（得到一个短促的拨奏声）和拉奏琴弦（得到一个平稳的持续声）之间的不同。
All sounds have a shape, and this shape is really important for what we hear.
The Life of a Sound
Every sound has a beginning, a middle and an end. All sounds change over time.
Changes over the life of a sound are described by the ‘envelope’.
Different sounds have different envelopes. The shape of the envelope affects the sound that we hear.
Composition Tip
The shape of a sounds envelope will affect how it sounds.
When composing try to use a range of sounds that have different envelopes. This will give your compositions a range of different sound types , and help you to create interesting contrasts (see also: Timbre).
Breaking down the envelope
To help us talk about sound envelopes we can break them down into four clear sections.
•Attack – The speed with which a sound begins.
•Decay – The time it takes for the attack to drop to a steady state.
•Sustain – A steady period in the life of the sound.
•Release – The gradual decay into silence.
Every sound will naturally have these sections, but in different proportions (N.B. some sounds will have only two or three of these section types).
The two most important aspects of the envelop are the Attack and Sustain. Let’s look at these in more detail:
Attack
Sometimes the attack might be very short, other times it might be long. The attack is one of the most important parts used by the brain when it tries to recognise sounds.
Fast Attack
This sound has a fast attack. Listen to how it very quickly begins. It has a very sharp and crisp sound.
Slow Attack
This sound has a slow attack. You can hear how it slowly emerges. It has a very soft and smooth sound.
Sounds with a fast attack are crisp, while those with a slow attack appear more smooth and rounded.
Sustain
Sounds that ring out have a long sustain.
Long Sustain
This sound has a long sustain. Listen to the steady tone.
But if we reduce the sustain we focus attention on the attack.
Short (or No) Sustain
The sound does not ring out, but begins to fade away almost immediately.
Sounds with a long sustain will ring out for a long time. Sounds with a short sustain will be very short and quick.
Listening Example: Bell
If we listen to the sound of a bell we can hear its long resonant sustain.
Original Bell
This bell sound has a long sustain, continuing to ring out for a long time as its vibrations slowly die out.
But if we dampen that same bell by pressing a cloth against it we remove all of that sustain and keep mainly the attack.
Dampened Bell
This time, the cloth prevents the bell from vibrating and ringing out. It dampens the sustain and almost stops it completely.
By dampening the vibrations with a cloth we have changed the envelope of the bell sound and highlighted the attack of the sound.
Extra Information About the Other Parts of the Envelope
The other two parts of the envelope – Decay and Release – also play a part in how a sound appears to us, but they are more subtle.
Decay
Release
Finally the sound fades out. We often pay a lot of attention to how sounds begin and ignore the way in which they end.
However the duration of “Release” can make a difference to the sound that we hear.
Short Release
This sound ends very abruptly. As if someone has slammed on the brakes.
Long Release
This sound gradually fades out with a slow smooth release.
A sound with a long release will last for a long time and gradually fade out. While sounds with a short release will fade quickly.
Transformations of the Envelope
Because the envelope is a really important property of sound, changes and transformations which affect a sound’s envelope have a big impact on the final sound that we hear.
Reverse
When we reverse a sound we flip the envelope. So the attack becomes the release and what was the release becomes the attack.
Original Sound
Listen to the envelope of this original sound. There is a fast attack, followed by a slow decay - sustain - release.
Reversed Envelope
This sound has been flipped in reverse, so the envelope is now backwards. In contrast to the original sound, we now have a slow attack, followed by a quick decay - release. (There isn't even really any sustain at all).
Reversed sounds are used quite a lot in different styles of music. The flipping of the envelope makes a big difference and can create some really fantastical new sounds.
Splice
Splicing a sound can allow us to remove or rearrange individual parts of the sounds envelope. By removing portions of the envelope, we can dramatically transform how we hear a sound.
Original sound
This sound has a clear and strong attack sound. You can hear the 'thwack' as the glass is hit.
Because the attack is one of the most important pieces of information used by the brain in recognising where a sound comes from, by removing the attack we can hide the source of the sound.
Attack Removed By Splicing
This sound has had the attack portion spliced off. We no longer hear the loud 'thwack' of the glass being hit, only the ringing sustain of the glass.
Removing (or transforming) the attack portion of a sounds envelope can help us to hide the original source of the sound, and can focus the listeners attention on different aspects of the sound.
Extra
The shape of a sound envelope is directly related to how an object vibrates and makes sound. The properties of the object and the way in which it is encouraged to make sound will all affect the properties of the final envelope.
For example: Think of the difference in sound between plucking a string (to get a sharp pizzicato sound) and bowing a string (to get a smooth steady sound)
Encyclopedia:
The shape of a sound over time.
This is a key parameter of sound and by changing the envelope we can radically transform how a something sounds.
A more scientific description of a sounds envelope is given by ADSR (Attack, Decay, Sustain, Release).
参看其它/See Also
术语翻译/Terms Translator
术语校对/Terms Proofreader
术语顾问/Consultant to terminology
参考文献/Bibliography
讲座/Lecture
评论/Comments
发表评论(预先注册)/Add comment on this term(members ONLY)