In response to requests, here is an Amplify / Fade effect that will fade the selected audio from one level (dB) to another.
Notes:
For some settings it is impossible to achieve both the selected fade shape and the selected target levels. To overcome this problem, the effect will automatically adjust the shape of the fade to produce a smooth transition that comes very close to the selected levels.
The fade results are mathematically accurate (given the above approximation), but may not exactly match what is intuitively expected.
The minimum time period over which the initial and final amplitude levels are measured is 2 samples (when the ‘time period’ is set to zero).
The length of audio that can be processed is dependent on the amount of available RAM. If the computer RAM memory becomes exhausted, processing will become extremely slow and may freeze Audacity.
This effect will appear in the ‘Effect’ menu, listed as “Amplify Fade…”
In comparison to the previous post, this is a more conventional Amplify/Fade effect.
Just like the standard Amplify effect in Audacity the amplify amount is set in dB (+/- 60 dB), but extra to the standard Audacity effect this plug-in can create a fade by setting one amplification amount for the beginning of the selection and a different amplification amount for the end of the selection. The amount of amplification between the beginning and end is extrapolated from the two settings according to the type of fade curve that is selected.
“Linear” fades are the default type and offer the familiarity of the standard Audacity fade-in/out effect but with the additional benefit of being able to fade “part way” rather than only fading to/from silence:
The “Round Curve” fade provides a rapid but smooth way to fade in a track, while “Logarithmic” fades produce a natural sounding decay.
The “Cosine Fade” creates an “S” shaped fade which is great for smoothly fading from one level to another or for producing a professional sounding fade-out. This fade type will often be the first choice for cross-fades.
When installed, this plug-in will appear in the “Effect” menu with the name: “AmpFade…” AmpFade.ny (1.88 KB)
And for why “fade to a target dB, not by an amount” (as requested with 16 votes on the wiki) does not work …
This plug-in does exactly as requested provided that the initial and final levels are not silent (“zero” cannot be amplified, so if the initial or final sample values are zero an error is given). TargetFade.ny (1.22 KB)
