Hi Harry,
I’m assuming that you’re asking about sound output from Ableton Live, but this advice would apply to any sound source that you want to plug in to a club’s sound system.
It’s common to find that the club leaves a channel available on their mixer for you to plug into. I’d recommend that you buy whatever cables you need to go from your computer to:
– Stereo RCA
– XLR
That would make you audible on most setups.
Anyone else?