Compressor threshold and input level

Audacity 2.3.1, macOS High Sierra 10.13.6.
Hi! I’m new to Audacity and learning the concepts. I’ve read that the compressor threshold is based on the signal strength being input into the compressor. How do I see that signal? The only meter that I can see working is the main slider output meter shown on top (the one with the speaker icon). The meter with the mic icon shows nothing during playback. If the compressor input signal strength is based on the “speaker” meter, then the threshold would vary based on where I put the main slider (which doesn’t make sense to me). Or should I put the main slider on zero, in which case the “speaker” meter would represent the input signal? Sorry if I have things way confused, but I’d just like to know where to look to see a meter showing the strength of the signal being input into the compressor so I can set the threshold correctly. Thanks!

Using the tools has always been a challenge because they seem to have an adjustment missing.

You might like RMS Normalize.

RMS is a standard electrical measurement (power transformers, wall sockets) that when applied to sound, happens to work out to loudness.


You can apply RMS Normalize to your show and force it to be the loudness of your choice. From there, you can apply all those tools that need a dependable starting point.

For one example, it’s not unusual for home voice performers to have harsh SS sounds or boosted sibilance problems. There is a perfectly lovely DeEsser tool, but it’s almost impossible to use without using RMS Normalize first. I thought the tool was a complete waste of time until I got all the ducks in a row—and the tools in the right order.

Is there a goal to your experiments? We publish an audiobook mastering suite of tools and testing to mimic the publisher’s testing. Not having to wait for the publisher to fail you can save a lot of time. Much better to fail yourself very quickly.