Sekunda, remember that the J48 is designed for 48v phantom power (the kind used for condenser mics). So whatever you plug into would have to have phantom power available. Some live mixers do, and some don't. And you'd be going to a mic level input and not a line level input. Some house mixers will have their mic inputs full, too.
By way of contrast, all but a few recording consoles do have 48V phantom power on mic inputs.
You'd want to make sure that whatever you're plugging into has phantom power available to use the J48.
For live use, I recommend a direct box with its own power supply (i.e., it doesn't require phantom power), so that it produces a line level signal, and not a mic level signal that needs a phantom power mic input on the board. You'd get more flexibility that way. These are often configured to go with both a mic level AND a line level output.
Also, they often have ground lift switches that can come in handy.