Difference between ratios in compression?


New member
Hi guys,

Can someone possibly explain the differences between setting the ratios as 3:1, 4:1 and 10:1. What difference would I expect with each of those ratios?

I use my microphone (RE20) for voiceover, no instruments or singing.

Which ratio is generally seen as the best for voiceover out of those three? Why do some people prefer 3:1 and some prefer 10:1? Why would someone choose one over the other? Is there a certain ratio which is recommended?



Well-known member
The ratio specifies how much compression is applied. At 10:1, the input must exceed the threshold by 10 dB for it to go 1 dB over the threshold at the output.

rob aylestone

Well-known member
Lots of people cannot hear compression, until the magic lightbulb moment, then you kick yourself for not realising it before. The trouble is the result is a formula. I dont use it on voice unless I have to, and if you have a breathy singer who makes a lot of noise on the in breath, that’s a great way to hear compression. The only thing I routinely compress is my bass, and it’s always two parameters, the slope so the way that big changes in playing volume get squashed into less. For my bass it will be 3:1 or there abouts because it cures a playing fault I have. When I’m a little unsure of the next note, i play it quieter. A bad habit I got into years ago. 3:1 seems to make these quiet notes sound more normal. usually the other parameter is threshold, as in when the compression starts, based on loudness. Singers can be quiet, or loud, and some work the mic and some don’t even notice there is a mic, so I personally do not have a set compression ratio and threshold. It’s what is needed for that voice, with that mic, and that song.

rob aylestone

Well-known member
They pick a value based on the voice, the mic and the working distance. There is no rule to follow. You pick the sound that works best for you. It will be different if you swap mic, person or distance. We’ve said this already. Recording is about your ears, not a rule book.