I see on the wiki that if you run Noise Reduction in a Macro and there’s no noise profile set, it’ll set it using the selection.
Is there a way to clear the saved noise profile? We have a set amount of silence at the start of each track, so I have a macro that selects the opening silence to create the profile, and then the whole track to apply the reduction.
But at the moment I have to close audacity every time I want to re-rerun the macro, and I often have to use it on multiple tracks in the same project. If I can clear the noise profile somehow, that’d solve this issue. But I can’t find any instructions on that.
No there isn’t (other than by closing Audacity). The noise profile can only be replaced, not cleared, but unfortunately it is not possible to do that with macro / scripting commands.
While this seems like (and is) a grievous omission, the reason is straightforward: The Noise Reduction effect was created many years before applying effects via macro / scripting commands existed. The Noise Reduction effect (previously called “Noise Removal”) was designed more than a decade before automating effects in Audacity was even considered.
Hopefully the Noise Reduction effect will eventually be updated to fully support scripting commands.
If you have, for example, an audiobook chapter reading with two seconds of Room Tone followed by the voice performance, could you not open just the two seconds, force a noise reduction, and then close the work without closing Audacity.
Open the performance by itself (may not be necessary) and apply Noise Reduction. Since there is an existing Profile, wouldn’t Audacity just apply that?
It will remember the last profile, if any. The only time it “forgets” a Profile is when you either update it, or shut down Audacity. Audacity opens fresh with no profile.
Stop me if I go astray.
I can generate a conspiracy scenario. If forced into it, Audacity will look at the whole performance, rip it apart, and assume any blobs of energy present for the whole performance must be undesirable (hum, buzz, hiss) or “Noise.” Build a Profile on that assumption.
Then hang onto it until either updated, or Audacity is closed.