Well then I, compression, even though I got it broadly, I am very far from an expert.

My opinion is just one of a kind which, in song:
- Was tired of direct feedback due to a too high volume because we did not hear him when he sang pretty low volume
- Was tired, conversely, the crests of farting when he drove a good face ...

This is where the miracle of dynamic compression, a pretty good idea in theory but is rather difficult to handle ...

Well no! With this compressor, there is rather easy.
- The first gate is knob (basically, if the input signal level is below the level you mentioned, it is literally off (gate mode) or attenuated (in expander mode)).
- The second knob, the sensibility from which noise the compressor must get going.
- The third knob, the compression ration: basically, it is hard left, no compression (the output level will vary between 0db and-infinity *), it is hard right, compression donf to (the level of output varira and therefore between-1db 0db *)
- The fourth knob, the output volume when the signal processed
- The 5th knob, a limiter (if your output level exceeds 0 dB, it will automatically reset to the desired maximum not to saturate)

This is for all 4 channels ...

Well since my song is compressed, it dismantled: the volume of my voice is much more homogeneous, it happens to cover the rest of the music no problem whatever the intensity of my voice ...

Therefore relatively simple child. The meters are of great help to set the camera.

on the other hand, high volume, it blows ...

But to begin in the compression is exactly what you need, not too many adjustments, or not enough

Also important: compressing your signal, you significantly reduce the chances of feedback ... since you do not need to put a volume of pigs when you play moderately.

And as usual Behringer, connections: input / output jack and XLR ...

* Figures intentionally incorrect, but if it can give you an idea ...