## Emphasizing Different Parts of a Sound ### Attack Time The attack of a compressor dictates how quickly the compressor reacts when a sound crosses the threshold. The attack time determines how quickly the compressor starts to apply compression once the signal crosses the threshold. You can think of a fast attack as compressing the initial part of a sound. By reducing the volume of this early part, you're often compressing the punchiest part of the sound, making it less punchy and more focused on the tail-end of the sound, which is more reverberant and ambient. This can give the sound more body and a fuller feel. On the other hand, a slower attack time allows the initial transient of the sound to pass through before the compression kicks in. This can retain the punchiness and impact of percussive sounds, making them stand out more. ![[07. Audio Effects/Compression/_attachments/image-6.png]] The release time dictates how quickly the compressor stops compressing after the signal falls below the threshold. A fast release means the compressor disengages quickly once the sound drops below the threshold. This setting helps maintain the natural dynamics of a track, but if not used carefully, it can cause a pumping effect where the volume level fluctuates noticeably. Conversely, a slow release means the compressor takes longer to stop compressing the audio, providing a more gradual and smooth transition. This can help blend the sound together, making it more cohesive. However, if the release time is set too slow, it can become musically inappropriate. The point of the compressor is to control loudness on a peak-by-peak basis. If the compressor stays active through multiple peaks, it won't re-engage when it needs to, resulting in less effective compression. ![[07. Audio Effects/Compression/_attachments/image-7.png]] ### Length of The Sound It is often helpful to visualize the attack and release time of compression in the context of the length of the sound. In Pro Tools, you can select a clip or a region of the timeline and examine the main counter area to calculate the length of time it takes to traverse that section. Being aware of this duration can be a useful tool in deciding on which attack and release settings to use, taking an analytical approach. See the video below for an explanation of how I discovered that the clip beneath is 337 milliseconds long. ![[Compression - Length of Sound.mp4]] ### Different Attack Times In the following video, notice how when I set the attack time to 10 microseconds, a lot of gain reduction occurs. However, when I set the attack time to 300 milliseconds, no gain reduction occurs. This is because the length of the audio clip itself is nearly that length, meaning the compressor is too slow to catch the sound. ![[Dyn3 Compressor - Different Attack Times.mp4]] ### Different Release Times In the video below, notice how the gain reduction resets quickly with fast release times. However, when the release time starts to approach the length of the sound, the compressor doesn't have time to recover before the next transient. As a result, the compressor clamps down unnecessarily, which is probably not musically appropriate for the situation. ![[Dyn3 Compressor - Different Release Times.mp4]] ## Curated Resources Watch this video to see attack and release utilized in the context of compression.  For more information, read [this Soundfly article](https://flypaper.soundfly.com/produce/how-to-choose-compressor-settings/) as well as the Attack and Release sections of [The Animated Guide to Compression](https://www.patches.zone/production-guides/compression-guide).