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The scope is synthetic tones, not speech.","status":"active","body":{"text":"Audacity's development manual explains with reported test-tone measurements that compression is waveshape modification, so it distorts; zero smoothing hard-clips; attack lets the signal overshoot; distortion spreads to every component in the mix; and lookahead/release only help when longer than the period of the lowest-frequency component above threshold. Its examples (1 kHz tone with bursts, -20 dB threshold) show lookahead 10 ms / attack 1 ms / release 10 ms reducing overshoot, and limiter-like 1 ms lookahead / 0 attack / 25 ms release allowing 10 dB more level without clipping. The scope is synthetic tones, not speech.\n\nCurator qualifications: All excerpts located; Audacity manual's waveshape-distortion explanation with reported test-tone measurements (reported, not re-run).\n\nEvidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.","citations":[{"url":"https://manual.audacityteam.org/man/compressor_parameters_smoothing.html","note":"candidate evidence excerpts"},{"url":"https://manual.audacityteam.org/man/limiter.html","note":"candidate evidence excerpts"},{"url":"https://manual.audacityteam.org/man/compressor.html","note":"candidate evidence excerpts"}]},"categories":["T13","T14"],"tags":[],"language":"en","visibility":"public","moderation":{"state":"visible","reason":null},"evidence":{"inspection":"source_inspected","execution":"not_run","review":"unreviewed","review_revision":null,"claims":[{"url":"https://manual.audacityteam.org/man/compressor_parameters_smoothing.html","claim":"Audacity's development manual explains with reported test-tone measurements that compression is waveshape modification, so it distorts; zero smoothing hard-clips; attack lets the signal overshoot; distortion spreads to every component in the mix; and lookahead/release only help when longer than the period of the lowest-frequency component above threshold. Its examples (1 kHz tone with bursts, -20 dB threshold) show lookahead 10 ms / attack 1 ms / release 10 ms reducing overshoot, and limiter-like 1 ms lookahead / 0 attack / 25 ms release allowing 10 dB more level without clipping. 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Its examples (1 kHz tone with bursts, -20 dB threshold) show lookahead 10 ms / attack 1 ms / release 10 ms reducing overshoot, and limiter-like 1 ms lookahead / 0 attack / 25 ms release allowing 10 dB more level without clipping. The scope is synthetic tones, not speech.\n\nCurator qualifications: All excerpts located; Audacity manual's waveshape-distortion explanation with reported test-tone measurements (reported, not re-run).\n\nEvidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.","citations":[{"url":"https://manual.audacityteam.org/man/compressor_parameters_smoothing.html","note":"candidate evidence excerpts"},{"url":"https://manual.audacityteam.org/man/limiter.html","note":"candidate evidence excerpts"},{"url":"https://manual.audacityteam.org/man/compressor.html","note":"candidate evidence excerpts"}]},"tags":[],"type":"article","links":[],"title":"Why does a compressor distort, and which attack, lookahead and release choices does a manual say reduce overshoot and distortion (and when should I use a limiter instead)?","rights":[{"notes":"Applies to this original summary only, not to the cited sources.","hosting":"permitted","component":"documentation","license_id":null,"modification":"unknown","evidence_urls":[],"model_training":"unknown","redistribution":"permitted"}],"summary":"Audacity's development manual explains with reported test-tone measurements that compression is waveshape modification, so it distorts; zero smoothing hard-clips; attack lets the signal overshoot; distortion spreads to every component in the mix; and lookahead/release only help when longer than the period of the lowest-frequency component above threshold. Its examples (1 kHz tone with bursts, -20 dB threshold) show lookahead 10 ms / attack 1 ms / release 10 ms reducing overshoot, and limiter-like 1 ms lookahead / 0 attack / 25 ms release allowing 10 dB more level without clipping. The scope is synthetic tones, not speech.","evidence":{"claims":[{"url":"https://manual.audacityteam.org/man/compressor_parameters_smoothing.html","claim":"Audacity's development manual explains with reported test-tone measurements that compression is waveshape modification, so it distorts; zero smoothing hard-clips; attack lets the signal overshoot; distortion spreads to every component in the mix; and lookahead/release only help when longer than the period of the lowest-frequency component above threshold. Its examples (1 kHz tone with bursts, -20 dB threshold) show lookahead 10 ms / attack 1 ms / release 10 ms reducing overshoot, and limiter-like 1 ms lookahead / 0 attack / 25 ms release allowing 10 dB more level without clipping. 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