2 active speakers into 1 subwoofer

Does the sub out say hi-pass or hpf or something? Or is that also just a link connector?

Based on what you describe, a crossover would be your best bet.

You’d run both your controller leads into the crossover, there you’d set one output to match the frequency range of the subwoofer and run a cable from that output to the sub. Then you’d run two cables to your L & R speakers.
You’d then have a mono sub (probably 125Hz and under – check specs/manual of sub for exact cut-off point) and stereo speakers.

By the way, in most situations pan effects aren’t all that important in dance situations, as people are not all facing the same way. Many clubs will actually run mono systems for just that reason and in the process cancelling out some other sound issues in complex or large spaces with multiple speakers.

Using a PA mixer (unless it has a built-in crossover, very uncommon on small PA mixers) is not helpful for you in this situation.

Correct. If you’d link the 12″s, you have the same signal come out of both (unless you are outputting mono from your controller it be either the L or R side).

Not giving advice on cross-overs, haven’t used active cross-overs in ages. If you have sub(s) and tops from the same manufaturer/series, they’ll usually have the cross-over in either the sub (my Mackie sub takes stereo in and then stereo hpf out for example) or the tops (I think QSC has speakers that will have sub out on their tops).

Only works if the speakers have sub-outputs. You describe them as link ports. This would imply that there are no crossovers in the 12″s. And the subs only have through ports also. So, whether you go into the subs first or the 12″ first, the link/through will supply full range signal to whatever you hook up behind it. And that is not the desired hookup.

Sorry, have to disagree.

Yes, the QTX sub has a crossover, meaning it will only play sounds below the frequency set with the frequency knob (you need to set this to a value that makes it work well with your tops, usually somewhere between 75 and 125 Hz). The input level knob lets you change the volume of the sound the sub produces.

BUT! The connectors next to the knobs are THROUGH (you can even read the word parallel in the white arrow that points from input to output connector). This means that the sub outputs the fullrange signal to the top.

And since you never mentioned brand/model tops you have, we do not know if your tops have frequency control/low cut switch or anything. Without that information I have to assume there is nothing there just an input and a linked output (also just passing the full range signal on).

This, by the way, is the reason I always advise to get subs and tops from the same manufacturer and from the same or compatible series. Things like phase, cutoff frequency and such are tuned to make the entire setup great. If you really know what you are doing, you can mix and match and find a working combination. If you really know what you are doing in that regard, you won’t be asking for advice on here though.

Give us the make/model of your tops and we can give you a final answer, but at this point I am saying that it’s not gonna work as a good 2.1 or 2.2 setup should work.

Yep, but no mention of a crossover/high pass filter. So my earlier assesment stands, that the subs send on the full range signal, meaning your tops still have to play all that low end too, meaning your balance between (sub)low and the rest will be most likely off (way too much low) and your tops will have to expend energy to play the low frequency material that the sub is already taking care off. Thus taking amplifier power away from the low-mids/mids.

Turning down the low eq on your tops may helps (some), but an EQ is not a filter, for one the slope is usually much less steep. It also depends if it is a shelving EQ or not, the center frequency of the EQ, the q-factor (how wide a frequency band is affected) and a few more tidbits.

My opinion is unchanged. This gear does not allow a correct 2.1 (2 tops/1 sub) setup without the addition of an active crossover. It will be a makeshift solution at best.