So it can reduce signal a variable amount, but can never boost it.

This is makes it VERY handy in a hurry, as there is one less thing to plug in & one less thing to cause a ground loop.

To keep the same level, you'll need to:

1) Turn up the signal on what you're plugging it into a bit (dj controller, dj mixer, portable pa, etc.). This is easy unless a) you're already maxed out on level or b) what you're plugging it into is very noisy to begin with.

or

2) If you're using wireless mics, turn up the output on the wireless receiver.

Sometimes you'll have a mic/line switch. You can experiment with switching to line, but that will be considerably louder. You'll have to turn down what you're plugging the Mini XLR Mixer into (dj controller, dj mixer, portable pa, etc.) as well.