Sooooo NOT a DJ! But need your assistance.

Hummm … wondering if I should … well … guess I will … here goes nothing.

To begin with, while adults have their own responsibility to protect their ears, when you entertain youngsters, that responsibility transfers to the parents (who are usually rather ignorant about the potential dangers) and the host (and through the host to anyone controlling the volume).
It pays to get a decibel (dB) meter (simple ones can be had as smartphone apps, not terribly accurate but sufficient for the purpose) and to start measuring the sound level at the closest place people will be to the speakers and at approximately the middle of the dance floor. Then look at a good decibel chart to see how long you can expose ears to that sound level before (potentially irreparable) hearing damage occurs. If you have it up to the level of a construction site for example (100dB), 1 hour is the max. Lowering it by 5dB to 95 it’s double that, still only two hours. But 5 dB lower in sound is a pretty big step (for example to add 3dB sound level you have to DOUBLE your power, i.e. from 100 to 94 dB is 1/4 of the original power).
The nasty thing here is that the actual results of the abuse might not show themselves until you are in your 40s or later and one day wake up with a ringing in your ears that doesn’t go away anymore and might just increase. It’s called tinnitus and it’s serious. Other trouble are early (partial) deafness, hyper-acusis (sp?) which is hyper sensitivity to certain frequencies and generally loss of tolerance for “normal” environment sounds, and early “old” hearing meaning you start to lose the high frequencies a lot earlier than you should.

If you want to be safe, you’d have to give all the kids a set of party plugs, they’ll still hear the music, but won’t hurt their hearing. Or you have to watch the max. volume very closely.

You picked up 1400W set speakers, which tells me … nothing. Is it 1400W for the set or each speaker. What size are the speakers (generally described as the number of inches of the low frequency speaker diameter, like 12″or 15″)? And Watts aren’t Watts, or rather “not all Watts are created equal”. Especially on low budget gear, marketing dictates that you use the highest variation of Watts you can get away with, typically between two and 4 times the RMS Wattage, which is a regulated quantity and which all serious speaker manufacturers will use. So, it’s very likely that your speakers are either 350Watt each or even 175W each (if the pair is 1400).

Something else you said makes me wonder about these speakers even more. You say they only have connection for a headphone speaker jack. This is where it really starts to worry me, as I don’t know of any PA speaker that takes that kind of input cord. Not saying it’s not what that is, but I haven’t heard of it.

Not clear is whether or not you DO want to hook up a DJ controller and if so, which one.

If we have the following information, we can give you a much better answer to your question:
* Brand/model of your existing PA speaker set (passive with amp if I read correctly)
* Brand/model of your new PA speaker set (active, i.e. amp built-in)
* Brand/model of your DJ controller, if any

Finally a word about speaker placement. Full range speakers always go to height where the high end speaker (tweeter in hifi terms) is slightly above head height. If you cater to kids, they could be set a bit lower of course to accomodate their height. The only exception is a so-called subwoofer which takes care of the very low frequencies. This type of speaker is optimized for use on the floor and benefits from it. Regular full range speakers will generally become very boomy when on the floor, incur what is called standing-wave problems making them sound bogus, but much more important, the mid high and high tones don’t get to the listeners ears too well and will most likely be soaked up by their bodies.

So yeah, putting them up is good. I would suggest getting regular height-adjustable speaker stands and buying after market sockets that you can screw on to your existing speakers. From a sound quality aspect this is way better than setting them on “big boxes”.

There you have it. Hope this helps in some way.

That still doesn’t solve her problem of wanting to use two sets at the same time. The amp might have balanced input/throughput, then what?

Ok, leave ‘m on the floor. Looks like they were “designed” for that. Frankly, the only thing imho they have going for them is that they are big. Which is nice for the eye, but does nothing for the “size of the sound”.

I’d have opted for a set of Numark Lightwaves, not too much more expensive, but I am guessing better sound quality, slightly more compact and with all the necessary connectors to make it all work. Pole mounting holes too. And link option to daisy-chain multiple together. And with the rebate action, not too much more money than those Pyle ones.

But hey.

It’s all pretty confusing. The main problem is that all connections (including the speaker hookup on the passive ones) are for hifi/home stereo use. There is not one single connector on there that you’d expect on something to be used as a PA.
Making it VERY hard to hook everything up the way you say you would like. Can it be done? Probably with some experimenting and expecting MacGuyver-like solutions (i.e. all kinds of splitter cables and adapters). Your best bet I think is to just hook up the big active ones and be done with it.