Digidesign's AIR Kill EQ is an equalizer that comes as a free plug-in with Pro Tools 8. It makes for an easy way to cut different bands of frequencies. While you can use it as a traditional EQ a bit too, it's not really made for that. You don't have to do any extra installation after you've installed Pro Tools 8, or upgraded from an earlier version, as it installs all of the free plug-ins during this process. In terms of the interface, it is very user friendly as easy to follow. As is the case with most free plug-ins, it has a simple interface so that just about everyone on all levels can use it without a problem. The plug-in has buttons to activate or bypass each of the three bands, as well as a knob for controlling your overall output level. The high and low bands have parameters for both gain and frequency, while the mid band simply has a knob for gain. There is also a sweep knob to control your bandwidth on all of the bands. A manual isn't necessary, and I'm not sure that they even have one anyway.
Thus far I haven't had any problems with performance when it comes to the Digidesign AIR Kill EQ. I just upgraded to Pro Tools 8 from 7.4 LE, and I'm running it on a Mac Book Pro that has a 2.2 Ghz Intel Core 2 Duo processor and 4 GB of RAM. I run Pro Tools 8 LE with both a Digi 002R or a Mbox Micro, depending on if I'm on the go or not. Digidesign's AIR (Advanced Instrument Research) Kill EQ is designed to take up a very little amount of processing power, which this does, so as long as you can currently run the plug-ins you have already on your system, you shouldn't have any issues at with this one.
While not a versatile equalizer of sorts, the Digidesign AIR Kill EQ is fine for doing simple jobs when you need to quickly cut out a certain band of frequencies. It definitely isn't my first choice to use, as I have a good amount of other plug-ins that I will always use before this one, but considering that it came free with Pro Tools 8, I can't do any complaining. I just prefer to use a traditional equalizer for any equalization jobs as it is just what I'm comfortable with. This isn't to say that I don't' use the Kill EQ sometimes, but mostly I stick with other equalizers even if to do a job like what the Kill EQ is for. If you're just getting started with Pro Tools, having a simple parametric equalizer on hand like this one is a great thing to have, especially at no extra cost...