Music Gear News
Compression: What It Is and How to Use It
What is compression?
Compression reduces the dynamic range available to an audio signal - the space between the softest and loudest sounds. Using a compressor can transform your music, bringing out otherwise hidden parts, by controlling the maximum levels of the piece and keeping a higher average loudness.
Basic compression parameters
These are common controls on all compressors. An understanding of these parameters should help you improve your audio recordings almost immediately.
Ratio: The degree of reduction of the dynamic range caused by the compressor.
The ratio represents the difference between the audio signal increase coming into the compressor, and the increase at the output. As an example, a 5:1 ratio would mean that a 5dB increase in the audio signal coming into the compressor would result in a 1dB increase in the output. It is a constant in that the ratio of input change to output change will always be the same regardless of how much compression is taking place.
Threshold: The level at which the compressor takes affect on the incoming audio signal. The compressor will have no effect on the signal below this level.
When a signal reaches or exceeds threshold level, the signals gain will be reduced by the amount the signal is greater than the threshold in relation to the ratio setting. Simply put, the threshold is the sensitivity of the compressor.
Knee: The precise point at which the compressor begins to reduce gain.
Hard Knee - the moment is sudden and definite
Soft Knee - a smooth transition from amplifier to compressor, allowing a wider range of threshold values to be effective.
Attack: The time the compressor takes before it affects the signal when it has breached threshold level.
Generally these times range from 1 millisecond up to a comparably slow 100 milliseconds. These settings are important in determining the final sound quality with respect to its brightness or high frequency content.
Fast attack - compresses the signal very quickly, affecting the gain at waveform level. The information transients at the front of the waveform provide affect the brightness of the sound, and so as a result using a fast attack can result in dulling the sound.
Slow attack - allows the front, transient section of the sound to pass through the compressor before it begins having too large an affect. If the setting is too slow, the compressor may be ineffective.
Release: The time it takes the signal to return from a compressed one into a normal, amplified signal once the audio drops below threshold level.
Release can range from 20 milliseconds to over 5 seconds generally speaking. It is important to use release carefully ? too fast a release with a short attack time can distort low frequency sounds.
Examples of compressor usage
Bass guitar: A compressor to add to the overall warmth of a bass sound. As a starting point try out a ratio of 5:1 with a medium threshold, medium attack and slower release.
Vocals: It is important to understand that each vocalist will require carefully tailored compressor settings to bring out the nuances in their singing. Try starting with threshold around 0dB, ratio of 4:1 and attack and release approximately in the middle. Adjust the output gain as necessary.
Hip-hop style compression: To get hip hop sounding bass and percussion sounds try a ratio of between 4:1 and 7:1 with a threshold of around 10dB to 15dB of gain reduction. Attack should have a different setting for each track in the mix. Begin by reducing it to its fastest level. Slowly increase the attack until the audio?s timbre dulls a little. Then, slowly again, decrease attack time until the original timbre has been restored. This is reversed for release settings. Again applying the release to each individual track, increase the release time to its longest level. Then reduce the release until the compressor can audibly recover before each note or hit. Too large a release will affect the gain of the next note.Posted on 30 Apr 2009 11:06 to category : Tips and advice
Related Music News
Don't leave it to trial and error. With a bit of research, you can find your perfect pair of drumsticks.
Gear4music social media competitions | terms and conditions of entry
Update available to improve performance and fix bugs.
Shure recently discussed how guitarists can achieve great results when recording at home or in a small project studio. We took a look and picked out our favourite points.
Some people could find the prospect of recording an electric guitar quite daunting, but musicians and engineers in fact have many options open to them.
Musicians who record at home to produce demos or professional quality recordings can build up a vast array of equipment to come up with their ideal sound. However, it is not just the instruments themselves that can determine how a recording turns out, as the engineering and production can potentially make or break a track.
Recent Music News
The HeadRush MX5: the most compact, powerful, and easy to use guitar processor to date...
RANE collaborates with A-Trak on a signature, limited-edition Battle Mixer.
Premium guitar. Built-in synth capabilities. BOSS announces an exciting new venture with its first-ever solo guitar project.
Akai MPC 2.10 update further reaffirms you can truly stand alone with an MPC
Our quest to find the ultimate Boss stompbox is over. Read more to see how close the competition got and win your very own pedalboard.
She kept us entertained during quarantine with the release of Folklore, but what's the secret to Taylor Swift's Long Pond Studio sound? We've picked apart the Disney movie to bring you the equipment you can use to recreate those bluesy folk tones.