Hl10027, There are several answers to your question. If you own an amp that is NOT an integrated amp, then you will need a control unit ( preamp) to drive the amp. Integrated amps are integrated because they include the amp and the preamp in one chassis.
If you are asking me why you need a "tube" preamp vs a "ss" preamp, then the answer is you don't need a tube preamp, you can certainly use a "ss" preamp.
I happen to prefer tube preamps to ss preamps, but that is a personal thing and may not apply to you. In fact, if I were you, I would seek out a tube preamp and go with a ss amp. The Concertino's do very well with tubes somewhere in the system, in the preamp section, IMO you will get the sound you are looking for and not have the heat and other nasties that a tube amp can bring to the table.
