I have been trying to save a recently-completed project to DVD and have discovered a curiosity regarding the DeNoiser I have applied to one of my audio clips in the timeline, or rather, its behaviour.
It is a little difficult to explain, so here goes, and if anybody needs extra clarification, please let me know.
In my project, there are a couple of sections of audio in my timeline which consist of old analogue audio, and it is quite hissy and could benefit from a little noise reduction. So, I have used the DeNoiser on both sections. On the first such section, I have set a -7.5 dB reduction, and on the second, a -2.5 dB reduction. I haven't encountered any problems with the second section, so the following refers to the first section only. This first section begins with very low level audio, then the volume increases after a few seconds. When I first open the project and play the low-level audio at the start of this section, the noisefloor setting has not yet been established (according to the display of the DeNoiser as I look at it), and this causes the audio to drop in overall volume. As soon as it establishes where it thinks the noisefloor should be, it is at the correct level. Then, when I play this section again, there is no drop in audio, as the noisefloor has now already been established.
When transferring the project to DVD without me playing this section first, so that the noisefloor setting gets established, the drop in audio will be present on the burned DVD of the project. If I play the section through, first, so that the noisefloor is established and, consequently, the audio does not drop during this initial low level few seconds of this section of audio, a burned DVD of the project (after doing this first) will come out without the audio drop (which is how I want it to be).
I would have thought that the settings of the DeNoiser at all stages of the audio sections, once played through, are 'set in stone', if saving the project at this point, and will then play back identically each and every time you play it through, but it appears that it is calculating where the noisefloor should be each time you play the project. So, depending on whether or not I have played this section through (when first opening the project), affects how the audio gets transferred on a burned DVD of the project!
Why aren't all the calculations of the DeNoiser settings on the audio section(s) you are using it with 'set in stone', as such, once played through the first time?
Just to say, I have opened the project again, today, and it now appears that this audio section does have the noisefloor setting established without me first having to play this section through, and the audio now plays, every time, as I want it to be (no drop in audio level at the start of the audio section). I don't know why it was behaving like this yesterday, maybe this audio section got corrupted along the way. Anyway, it seems OK now, but I don't yet fully understand exactly how the DeNoiser is supposed to behave in your projects - between the time when you first apply it to one of your audio sections, up to the time when you burn the project to DVD. Maybe the DeNoiser settings are 'set in stone', as such, in your projects, and this temporary behaviour with the DeNoiser, yesterday, caused me to have doubts about this.