Another day, another question ;)
 
How do people use several pairs of monitors if your mixer only has 1 monitor XLR output?
 
My situation would be 1 pair of studio monitors, a pair of PA monitors and a pair of normal speakers.
 
So the studio speakers would be for mixing and playback, the normal speakers for playback (how it would sound in one's livingroom and the PA for rehearsal. So is there a way to switch between these sets instantly, without removing cables? I can imagine there must be some kind of hardware switch for at least the XLR sets but what about the "normal' speakers that usually just have an open cable you need to insert in the back of your reciever? I can't really find a solution for that
 
As always, any help is greatly appreciated!
 
Edit: I'm looking at the Driverack 260 as i need something similar anyway for my PA system. Would this switch between at least my mixing monitors and the PA monitors?

https://www.sweetwater.com/store/detail/Source
 

Thanks for your answer. But 900 dollars is way, way beyond my budget for this. So i hope there are cheaper options. I find it hard to believe that everyone who runs 2 or more speakers paid 900 dollars to do this.

I use this:www.sweetwater.com/store/detail/SLW333
 
But it is only 1/4" Tip-Ring-Sleeve (TRS). They do have adapters to go from XLR to 1/4" , but it could introduce noise or ground loops depending on what you are connecting.

Somanyquestions
Thanks for your answer. But 900 dollars is way, way beyond my budget for this. So i hope there are cheaper options. I find it hard to believe that everyone who runs 2 or more speakers paid 900 dollars to do this.

If you buy the Hosa until I'll make you TRS to XLR adapters for only $700US.

Is there a brand and model of the mixer in mind or is this just a general question.  For specific mixers this sort of information enables people to help much more so.  Block diagram and manuals can be downloaded and checked.  
 
Generally though there are probably enough outputs to feed your main speakers for the PA, a set of other outputs of some description to drive studio (active I assume) monitors (e.g. Control Room Out) and the foldback sends driving your foldback system. All without patching. And there will be separate master controls feeding each of these scenarios. It would be a simple matter to adjust the send level to the required outputs. 
 
A lot of decent PA/studio mixers would have built in features that would be similar to what the Dangerous Music Source can do. That is good for connecting to a DAW to give all that input output monitoring connectivity for a computer plus a variety of other input sources.
 
A powerful combination if you can afford it would be the Dangerous box and a nice live mixer feeding a PA and monitors. Then the computer could be patched directly into the PA mixer.  Otherwise your interface attached to your computer will work fine as it is next to the PA mixer.
 
I have often done multitrack recordings and operated a PA at the same time.  What works real well there though is to use a fast interface on your computer. All the input sources go to them first then into the software.  With a good interface extreme low latency is possible and it is fine to have the PA being fed from special buses within the software. Without any perceivable delay. More interesting PA monitor mixes can bet set up that way. But sources can also go direct to the mixer and use the direct outs from the mixer to feed the DAW as per the more often conventional way. 
 
I would be looking for the PA mixer have the capability of sending separate channels digitally to your DAW as well. This will make multi tracking a snap too. There are some e.g. Presonus and these all work as a full PA mixer and with Studio One capture software making it simple and easy to capture everything live. 

I've been using a Samson C-Control for 2 or 3 years.  No XLRs, but it works great.  I don't use all of the features - mainly the multiple speaker/source selection capability.  $99 new ...
 
oops.  Discontinued.
 
 

Even my little Yamaha 6 channel MX mixer has Balanced out for mains, Balanced out for studio monitors and RCA out that can feed a home stereo. Hard pressed to find a mixer that doesn't. The Monitor out has it's own volume but the RCA is always on at Unity. TRS is balanced same as XLR. 

Somanyquestions
Another day, another question ;)
 
How do people use several pairs of monitors if your mixer only has 1 monitor XLR output?
 
My situation would be 1 pair of studio monitors, a pair of PA monitors and a pair of normal speakers.
 
So the studio speakers would be for mixing and playback, the normal speakers for playback (how it would sound in one's livingroom and the PA for rehearsal. So is there a way to switch between these sets instantly, without removing cables? I can imagine there must be some kind of hardware switch for at least the XLR sets but what about the "normal' speakers that usually just have an open cable you need to insert in the back of your reciever? I can't really find a solution for that
 
As always, any help is greatly appreciated!
 
Edit: I'm looking at the Driverack 260 as i need something similar anyway for my PA system. Would this switch between at least my mixing monitors and the PA monitors?

I use this https://www.sweetwater.com/store/detail/SLW333
 

This is a bit more $$ but the extra features (mono/stereo, mute, solid build) have proven to be quite useful in a small project studio.
 
http://new-old-sound.com/products/31-mcone-b
 
Patched in with TRS > XLR cables, no noise issues.