The Mackie MR8 is sold as a single studio monitor that doesn't need an external power supply as it is an active monitor.  They aren't huge monitors so I would say that they are best suited for monitoring and listening rather than mixing, but this isn't to say they they can't be used for mixing - they just aren't best suited for it.  The Mackie MR8s have XLR connections and well as some EQ settings, and can be plugged into the wall with a simple power cord.


SOUNDS

The sound of the Mackie MR8s is a really good sound for studio monitors of this size.  While they do have a pretty full sound, since they aren't huge monitors they lack a certain low end presence, but as long as you take this into account while mixing you should be okay.  The stereo image is fine and they dynamics are as well.  Beyond the low end, the sound is precise across the frequency spectrum and I would definitely describe the sound as full and clear. 


OVERALL OPINION

Overall, the Mackie MR8s are a really solid set of studio monitors.  While my use with the monitors is not extensive as I have only used these a limited number of times, in my time using them I have definitely come to respect them.  I've always been a fan of the monitors that Mackie makes as they are very reasonably priced and sound great, which is the deal with these speakers.  They are quite cheap considering the good sound that you can get from them.  These definitely aren't the best monitors out there, but they are very solid for home studio owners.  I can't say they are up to par with the best studio monitors that I have used out there, but they do sound good and you can get them at a great price.