@yek , what is your mixing board? A popular method of implementing subwoofers is to feed them via an extra Aux send (mono). With digital small format mixers like the Mackie DL1608 or the Behringer XR-18, you have additional processing options (discrete Aux EQ/limiting) which can help you fit the subs into the mix with more versatility, and use a HPF to fine tune the crossover point perhaps lower than the factory spec - you may or may not need to engage the SUB switch on the CLRs, but let your ears be the guide.
The idea behind this is: the vast majority of channels don't benefit by subwoofer content (vocals, traditional guitar sounds, horns, and drums - other than kick and low-tuned floor toms). Thus, by only adding (via aux send) the channels that have desired subwoofer content, you'll be using the subs efficiently, with less worry about HPF-ing all the other channels to keep their content clear of the subs.
So, bass guitar, keyboards (maybe, if the left-hand keys don't create a sonic space war with the bassist), kick drum, floor tom(s), and break/pre-recorded music are the only things you'd want to feed the subs. Then you can gently bring the sub level up and down as desired, without its level being tied to the Mains L/R level controls OR EQ/dynamics processing.
A side benefit is that you won't need to be concerned about having to "jumper" from the subwoofer to the L/R speakers, which IMO, is just a cleaner way of doing things.
OTOH, if you don't need that amount of fine tuning where subwoofer volume isn't so thunderous, the advice already provided is all good.