how does one send the signal to a sub or bass amp and also the Bose Compact. I have a Yamaha cx82 mixer.
Since the cx82 has no dedicated sub out, and you are using the Bose Compact here's the way I'd do it. Plug the L&R main outputs from the mixer into the 2) rca jacks on the Bose. This will sum the channels to mono and fatten the sound. Use the monitor send to feed a sub (or bass amp). This way you can add punch to whatever channel you want to have more bass. If you're really pumping the volume, maybe try rolling a little bass of the Bose outputs to free some headroom and add more monitor send. On the bass amp's controls, roll off as much of the highs as you need to in order to get a low, thumpy, non directional tone. Bass is best when it rumbles your stomach, but you can't tell where it's coming from.
There is also an output on the Bose itself, but I never had a reason to use it yet. You could feed that straight to a bass amp too.