The Mytek Private Q is a headphone amplification station that is amongst a larger system designed by Mytek.  This is probably the most complete headphone monitoring station that I have seen.  It offers the most flexibility in terms of monitoring while recording because you have control over 10 different levels at once, which is more than any other system I have seen and is usually enough for controlling every possible instrument in a mix.  You not only have control over the level, but also control over the panning, and of course there is a master volume knob as well.  All together the system has 8 mono and two stereo channels.  In back of the device there are a slew of connections including XLR, 1/4 and while I'm not sure what the large connections are called, they are for hooking it up to your console.  It also has a little radiator on the back of it as it can get pretty hot.  As an artist, it is great to have this while monitoring as it really allows me to set everything exactly as I want it, and as an engineer it always seems artists love having the ability to use this.  It is also great that they leave space under the knobs so you can put tape to label everything, as things will of course change from session to session.  The only downfall of the Mytek Private Q sysem is that it is quite expensive, so for this reason I would only suggest this for professional studios.  That being said, I really feel that no professional studio should be without these as they are really that good.  Overall, the Mytek Private Q headphone system is a pleasure to use and is something that every studio owner should be aware of and consider.