Right then.
Part of the application of Steve's Limiter is following it with Effect > Amplify to -3? Or is that only if I'm preparing client delivery?
I think that there are two versions of the same limiter effect. Mine has just the option to bring the level up to 0 dB after completion.
Thus, the multiple applications of the limiter aim for an Rms over -20 dB (ideally -17 dB), followed by a -3 dB amplification eventually.
However, it needs a test mp3 export to determine the actual track gain. I had to set the peak level to -2.7 dB in order to get a mp3 with -3 dB after re-import and decoding.
That's actually the part that annoys me a bit. Firstly, that Acx works with mp3 as base for further encoding and secondly that this format changes the properly set levels so randomly.
I accepted the latest submission and ran it through what I perceive to be the accepted process, and I got the -60 noise and the -3 peaks in good order, but I didn't get the high RMS value. It's still-25dB or worse. Are we applying multiple 3dB Steve's filter one after the other? Where do I set the Release Time?
Do you refer to the "hold" slider? I can't recall right away how the three settings (rise time, fall time and look ahead) are calculated from this single setting. The release time is normally 4 times as long as the attack and the look ahead is the max value of the two.
Isn't it the case that the work has to achieve at least -23dB RMS after the peak adjustment to -3dB? Do I perform the Contrast tool measurement and then extrapolate where it's going to end up?
Koz
Certainly, the -3 dB has to be taken into account.
As I said before, I run my own kind of compression first over it to bring down loud passages, e.g. direct speech and exclamations.
Although it works with Rms levels, some coinciding peaks are sometimes attenuated too, e.g. the audio goes down from 0 to -3.8 dB.
The limiter is then multiple times applied to bring down extraneous peaks. Still, the goal is -15 to -20 dB Rms (from 0 dB peak level seen).
Although the noise removal should be applied early, I usually put it off because such huge Rms changes (10 dB and more) raise the noise level again into audible regions (since the limiter has no noise floor fall-off).
Thus, one has either to reduce the noise level in the beginning with the offset added, or to do the noise reduction twice or to do it in the end, whatever fits best. It surely depends on other effects that are applied inbetween--highpassfiltering, click removal, de-essing, equalization...
Koz, I think you should build up the audiobook checklist as a flow diagram with several questions and the underlying decision branches.
If you require help using Audacity, please post on the forum board relevant to your operating system:
