# How to use compression - Basics - About ratio

## Determining the compression amount with ratio

Previously, we determined
at what point compression starts via threshold. ↑ In this way,「threshold」with determine what area will be compressed (above the threshold).

However, the「threshold」is just a line.

The parameter that actually applies compression is the「ratio」. 「Ratio」takes the sounds that are past the「threshold」,
and determines「what fraction of it remains」.

The higher the「ratio」the more sound is compressed. ↑ If a number going over the threshold were to be 100
When ratio is set to 2 – the sound would be 1/2 = 50
When ratio is set to 4 – the sound would be 1/4 = 25

When you want to keep the volume in check and keep the overall volume similar,
set this「ratio」higher.

## Sound comparison

Lets compare some actual sounds:

Original sound

Ratio 2 (1/2)

Ratio 8 (1/8)

The higher the ratio is set, the more the sound will sound “squished.”

The 「compressed sound」refers to this phenomenon,
and refers to the change in tonality due to the compression.

However, compressors are a hard effect to hear if they are actually being applied.

If you are unsure how to set your「ratio」,
set the amount to「4」for the time being, and move the threshold around to see how much compression you want applied to the sound.

In our next article, we will take a look at why volume seems louder when compression is applied.

Enjoy!