Fast attack catches and suppresses transients; slow attack lets them pass through before compression engages

The attack time controls how quickly the compressor clamps down after the signal crosses the threshold. A fast attack engages almost immediately, catching the initial transient of a sound — the hard consonant of a vocal word, the click of a drum hit. This can tame aggression and bring the sound forward in a calm, consistent way. A slow attack lets the transient escape through before gain reduction starts, which preserves the initial impact: the transient punches through, then the body is compressed. For a vocal, slow attack = more forward and intimate; for drums, slow attack = more punch and snap. The same signal, two different presentations — both are valid depending on the aesthetic goal.

Examples

Compress a snare hit. With fast attack: the crack is caught, the snare sounds controlled. Increase attack to 30ms: the initial crack punches through and the body is compressed, giving more impact.

Assessment

What is the audible result of a very fast attack versus a very slow attack on a drum transient? For a lead vocal you want to sound intimate and upfront, which direction would you push the attack?