There's nothing really to operating this DI box as it is just as simple as using any other DI box out there. Simply plug in your connections and let it do its work. Having the ground switch is a big plus as it comes in handy a lot as is the boost switch. Beyond this there isn't much to say about using this DI box except for how easy it is! I've never seen the manual for the Demeter VTDB-2B Tube Direct Box, but one isn't necessary as you can figure it out without one.
The sound quality of the Demeter VTDB-2B Tube Direct Box is really clean and this box definitely does the job well. I mostly use this for recording bass guitar and digital keyboards but it is suitable for anything that you would want to record direct and is also great for live shows. Since it has real tubes in it you can definitely hear them at work producing a very warm tone, but at the same time your signal will be clean and you will be hearing exactly what the signal is. There aren't too many direct input boxes out there that have real tubes in it, so that is a big plus when it comes to the Demeter VTDB-2B Tube Direct Box.
I first used the Demeter VTDB-2B Tube Direct Box about a year ago and it has become one of my favorite direct input boxes to use. Even though I don't have access to it all of the time, when I do it is always a pleasure to use because I end up getting a perfect direct sound for what I am trying to do. Since this is a pretty special DI box, the price of this unit is quite expensive and unless you are a professional I would stray away from it because of this heavy price tag. However, this is pretty much a perfect DI box besides the huge price tag and if you are professional looking for top notch sound regardless of the price, the Demeter VTDB-2B Tube Direct Box is a great way to go!