By the way I want to also add that once made himself at home tube amp with my own hands, I will say that more than anything else I do not want. I liked the sound so that I fell in love with him. But this is not propaganda. each has its own tastes!
Here are some "pros" and "against" tube amplifiers:
- Smooth transition into clipping
- Large dynamic range (because the clipping is not so much at full capacity);
- The overloaded sound (overdrive) - "Music" (ie, soft, not sharp);
- Different models offer continuous recognizable sound;
- Limited bandwidth (amplifier and speaker in combination usually produce about 80-6000 Hz).
- The amplifiers have a lot of weight because of the need to install the output transformer and large power transformers;
- Lamps are usually necessary to replace up to once per year to maintain optimum sound;
- Lamps "noisier" (hiss, microphone effect);
- Amplifier bask in the paper (and only few have cooling fans!)
- Roads in price and content.
But what to use preamp: the transistor, lamp, or effects processor is up to you.