Audio compresion

Post on 24-May-2015

157 views 1 download

Tags:

Transcript of Audio compresion

The Compressor effect reduces the dynamic range of audio.

One of the main purposes of reducing dynamic range is to permit the audio to be amplified further

(without clipping) than would be otherwise possible.

Therefore by default the Compressor amplifies audio as much as possible after compression.

Equipment use :

• Software : Audacity 2.0.3 (free)

• Behringer mixer Q 1202 usb

Audacity go to menu – effect - compresor

Audacity Compressor The resultant increase in average or RMS level can be useful for audio played in a noisy environment such as in a car, or in speech, to make a distant voice sound as loud as a close one. Because the gain changes relatively slowly, a compressor does not distort the signal in the way that a Limiter or clipping would do.

Threshold

The level above which compression is applied to the audio and in audacity there is Noise Floor is The compressor adjusts the gain on audio below this background level so as to prevent it being unduly amplified in processing. This is mainly useful when compressing speech, to prevent the gain increasing during pauses and so over-amplifying the background noise

Ratio:

The amount of compression applied to the audio once it passes the threshold level. The

higher the Ratio the more the loud parts of the audio will be compressed. The Ratio sets the slope of the blue line on the graph above the

threshold. Tips : 2:1 setting good for most recording

Attack Time:

How soon the compressor starts to compress the dynamics after the threshold is exceeded. If volume changes are slow,

you can push this to a high value. Short attack times will result in a fast response to sudden, loud sounds, but will make the

changes in volume much more obvious to listeners. Tips : 0.2 is just fast enough for voice recordings

Decay/Relase Time:

How soon the compressor starts to release the volume level back to normal after the level

drops below the threshold. A long time value will tend to lose quiet sounds that come after

loud ones, but will avoid the volume being raised too much during short quiet sections like

pauses in speech.

Gain Reduction

• Apply Gain after compressing option checked. This will increase the overall volume of your recordings slightly and, in many cases, help alleviate any sound drop outs.

Before compression After compresion

https://soundcloud.com/firman-mulyadi/word

Behringer Q 1202 usb

Compression limits the dynamic range of a signal, lowering the level of loud sounds and

turning up softer sounds to achieve sonic balance. But applying compression is a delicate

art that many novice, and even intermediate sound techs have difficulty mastering

Using the COMP knop to adjust the amount of compression effect on the channel this will limits

the dynamic range of the audio source

End of Slides