Control attack and decay
See this course’s project requirements
Three original short generated sound effects with waveform/frequency plans, controlled amplitude envelopes, checked WAV exports and use notes; no microphones or licensed samples required.
Keep your working files in your own notebook or software. Save a private description, checklist, and work link in My Proof.
What to include
- Write three event briefs with measurable parameters and nonaudio equivalents.
- Generate original tone/sweep effects with onset/release plans.
- Calculate layered peak bounds and retain digital headroom.
- Deliver three actual WAV files with format/duration evidence.
- Distinguish generator tests, native editor checks and optional listening.
Review and revise
Use these criteria to check your work and choose what to improve.
- Design: parameters serve a stated fictional event.
- Signal controls: frequency/envelope/peak reasoning is correct.
- Artifact: headers/frames match the stated output.
- Evidence: listening/native limits are accurately reported.
Want more background?
The idea in everyday life
Attack is the onset rise; release is the fade toward the end. The supplied Python fixture uses explicit linear ramps reaching zero at both endpoint samples. Audacity’s amplitude-envelope points do not generally reach exact zero; use its documented fade effects when that is needed and inspect any later effect that may discard envelopes. These routes are related but not identical tests.
A ramp controls how a sound begins and ends.
Control attack and decay — worked practice
A ramp controls how a sound begins and ends.
Original Confirm duration 0.4 s: attack 0.01 s; release 0.12 s; peak 0.35. A linear attack reaches 0.175 at 0.005 s if the sinusoid happens to be at unit magnitude, so this is the envelope limit, not every actual sample’s value. Fixture test checks first/last samples near zero and peak≤0.35. Abruptly cutting a nonzero sample can produce a click; endpoint ramps reduce that discontinuity.
1. 4.1 Control
Draw the amplitude-limit envelope with onset 0, attack endpoint 0.01 s, body and release ending 0.4 s. Keep the envelope separate from the oscillating waveform.
You should see: The envelope describes a bound over time.
2. 4.2 Control
Use fade/ramp controls or the provided fixture to implement the plan. Record the actual route; do not claim Audacity control points reach exact zero automatically.
You should see: The implementation route is explicit.
3. 4.3 Control
Inspect the beginning/end sample behavior and the peak bound. If using native effects after an envelope, recheck the rendered result rather than assuming the curve survives.
You should see: Endpoint and peak evidence is checked.
4. 4.4 Control
Change attack to 0.02 s with the same 0.35 peak. Calculate the envelope limit halfway through that attack and preserve the changed plan.
You should see: At 0.01 sinto the new attack, envelope limit 0.175.
What to finish
An envelope plan with endpoint/peak checks and a changed-attack variant.
Watch for this
Treating an envelope-limit value as the exact oscillating sample, or assuming every native effect preserves envelope points.
How can I tell I understand it?
You can distinguish the designed ramp, actual samples and native-operation limitations.
Quick knowledge check
Answer all 3 questions. Get at least 2 right and the lesson completes automatically.
You’ll get an explanation for each answer. Signed in? Your results save to your account.
Pass the check. We’ll save the progress.
Answer all 3 questions above and get at least 2 right. You can review the explanations and try again.
Go to the knowledge checkTools, templates, and lesson sources
Tools and templates
Tools open in a new tab so you can keep your place here.
Sources and further reading
Explore the references behind this lesson.
Source & access notes · checked 2026-10-01
Read control-point amplitude changes, envelope zero limitation and effect/render caveat. Python fixture uses explicit linear ramps, not a false claim that Audacity envelope points reach exact zero.
Access: Public page text or PDF was opened and read through the web reader on 2026-10-01; no signup required for reading.
Reuse: Linked for further study. All LifeStarter scenarios, samples, assets and assessments are original; no source exercises or artwork are copied.
Source & access notes · checked 2026-10-01
Read mono sample width/framerate/write frames and header/frames semantics; original dependency-free generator is tested separately.
Access: Public page text or PDF was opened and read through the web reader on 2026-10-01; no signup required for reading.
Reuse: Linked for further study. All LifeStarter scenarios, samples, assets and assessments are original; no source exercises or artwork are copied.
Report a problem with this lesson
Tell us what went wrong. Please leave out personal information and private project contents.