Normalize effect and Loudness normalizer effect: Difference?

It just feels like you’re trying to read for audiobooks. Did I hit it?

Effect > Amplify works from blue wave tips and peaks. Effect > Normalize used to as well with a couple of additional variations thrown in such as DC removal. Loudness Normalize is very different. The two variations are RMS and LUFS.

RMS is pretty simple. It’s an electrical measurement of horsepower energy in a wav. It’s always lower value than peak and it’s the lighter blue pattern in the Audacity timeline. Electric motors don’t care at all what the peak values of their power are. They need the RMS energy to turn.

You can measure your performance RMS value with Analyze > Contrast > Measure Selection.

It’s also, usually much more importantly, how ACX measures your audiobook voice volume.

LUFS or Loudness Unit Full Scale is similar to RMS, except it takes into account your ear sensitivity. That one is the difference between low rolling thunder on a summer evening and baby screaming on a jet. The thunder is louder, but LUFS isn’t fooled for a minute.

Audacity publishes ACX Check which is a tool that measures the three Audiobook technical specifications. Peak, RMS and Noise.

We publish other audiobook tools, too.