Music Production
Convert ADSR envelope stages to milliseconds using tempo.
Plan envelope timing with tempo-synced values.
ADSR envelopes are fundamental to sound design and synthesis, controlling how a sound evolves over time after being triggered. ADSR stands for Attack, Decay, Sustain, and Release—four key stages that shape the amplitude contour of sound. Attack defines how quickly the sound reaches full volume, decay controls the initial drop in level, sustain sets the steady-state volume, and release determines how the sound fades after the note ends. Understanding ADSR envelopes is essential for creating expressive synthesizer patches, realistic drum sounds, and nuanced instrument performances. From punchy percussion to smooth pads, ADSR parameters form the backbone of dynamic, musical sound design across all synthesis methods.
When you trigger a note, the envelope immediately enters the Attack phase, ramping amplitude from zero to peak over the specified time. Once the peak is reached, it transitions to Decay, dropping to the Sustain level. The sustain phase maintains a constant amplitude for as long as the note is held. When you release the key, the Release phase begins, fading the amplitude to silence over the specified duration. Each phase is independently controlled, allowing infinite creative possibilities—from instant snappy attacks to smooth, tape-like fades.
Total envelope time = Attack time + Decay time + (Sustain time when held) + Release time. Phase transitions are typically linear or exponential curves. Logarithmic or exponential curves provide more natural-sounding, musically smooth transitions than linear ramps.
Linear envelopes rise or fall at a constant rate, while exponential (logarithmic) curves follow how human perception of loudness works. Exponential curves sound more natural and musical, especially for amplitude envelopes, because they mimic how analog synthesizers and acoustic instruments behave physically.
Percussion and drums need fast attacks (0-50ms) and short decays (50-500ms). Pads and ambient sounds benefit from longer attacks (500ms-2s) and sustains at lower levels. Bass sounds typically have fast attacks with longer decays. Experiment and let the musical context guide your choices.
Absolutely! Pitch envelopes control how frequency changes over time—common in bass synthesis, where a pitch envelope dip creates the classic 'wobble' effect. Many synthesizers allow you to apply envelope generators to any parameter: filter cutoff, resonance, pan, effects depth, and more.
The sustain level is only reached after the decay phase completes. If decay and sustain times are very short, the sustain level barely matters. But with longer decay times, the sustain level becomes crucial—it defines the equilibrium amplitude while you hold the note, essential for realistic instrument modeling and long held notes.
