RMS Normalizatiton & Limiter Issue

Well Hello There, I’m back. Running 2.3.3 in windows 8.1 for ACX Checks on auditions. On ACX Check, passed the Peaks and Noise Floor Levels but RMS was off. Ran, as suggested previously, the RMS Normalization (set at -20dB) and Limiter (tried both -3.00 and -3.50 settings) and that gave me a Noise Floor exceeds -60dBFS error. How do I remedy that? I went thru the Plug-Ins and briefly saw one that said rms (New) but when I went back to copy it in Effects, it was gone. Any assistance will be much appreciated.

Limiting just affects the loud parts so it doesn’t change the noise floor.

But, normalization is a linear volume adjustment so if normalization ends-up boosting the volume by +6dB, the RMS & peak levels will increase by +6dB and the noise floor will also come-up by +6dB.

The [u]Audiobook Mastering Outline[/u] has some tips for noise reduction, and the standard low-frequency roll off may help too (if you’re not already doing that).

Of course, it’s best to prevent/avoid noise* in the first place as much as possible and it helps to get a “good sound level” into the mic (if you’re not getting that already) for the best possible signal-to-noise ratio.


  • Most “home studios” are not soundproof or quiet-enough to pass noise without noise reduction, and sometimes “home equipment” generates a little too-much electrical noise too.

Audiobook Mastering, as above, is a suite of tools designed to work one after the other. You are warned not to take the tools out of order or leave any out.

The first step, Filter Curve tries to suppress low pitched rumble sounds, an error that many home microphone have. That right there can be the difference between passing noise and not.

Home readers never pass noise. We live in insanely noisy environments and nobody notices until they need to measure it. For one common example, can you tell if your computer is on just by listening? Kiss of death.

It’s enticing to depend on Noise Reduction and other filtering to get you past ACX Check, but Audible is waiting for you. They have a failure called “Overprocessing,” where your voice is tight, bubbly, gargling or echoey from processing. Nobody is going to buy that as an audiobook and they won’t pass you.

So you have to do it in real life.

Post a voice sample on the forum. We can sometimes identify where your noise is coming from and suggest solutions.