I'm applying a DeNoise effect on my sound. However I get a different result depending if I apply it to the track or to the clip. It seems to be way more efficient when it's applied to the clip. Is that normal? I'd prefer to be able to use on the track since I have quite a few clips I need the effect on.
The "Denoise Effect" depends upon the user "teaching" the software what is the unwanted "noise", by letting it listen to a sample of that noise and so create a Noise Profile. Once the profile is "learned", that, and only that, is what the software will seek to remove.
So, if the "noise" doesn't really vary in character between your various clips, there is no reason why applying the effect as a Track Effect will not, in theory, work. However, almost inevitably, the "noise" will vary between clips, I think. Hence why applying NR as a Clip Effect, and creating a new Noise Profile for each clip, will produce a more satisfactory output.