The Orban 516 EC is a hardware de-esser, consisting of three channels and a very simple make up. It is an analog piece of gear, and I'm not sure what types of connections it has since the one that I used was already racked up and ready to go in the studio where I used it. To make the connections, it was already hooked up to the patch bay for easy access. It is rack mountable and will only take up a single space in traditional casing.
Using the Orban 516 EC is incredibly simple to do. There is only one parameter to control the level of de-essing on each of the three channels, as well as one to engage each of the channels. As anyone can easily tell just from looking at it, there isn't much to know about the 516 EC. This is definitely something that I like about this unit, as it makes it quick and easy to de-ess. The manual is useful for checking out the schematics, but isn't necessary for any other sort of use.
The sound quality of the Orban 516 EC definitely makes it more than useful. It does a very good job of de-essing, but doesn't offer up too many parameters so it isn't all that versatile. Of course this is only going to be used for vocals, but it would be nice if there were some other parameters on this to make it easier to adapt it to different types of vocalists. Either way, the 516 sounds clean and does the job well and very quickly.
While I generally use plug-ins to de-ess nowadays, when I do have access to the Orban 516 EC, it is definitely something that I will use as it has a more realistic sound than most of the de-esser plug-ins out there. I can't say that I'd recommend going out and seeking one of these out since they would be hard to find, but if you do come across one and are in the place where you'd like a hardware de-esser, the price should make it cheap enough where you can try it out to see if it will be helpful for you.