A hybrid amp with a tube front end and solid state output stage is a good idea if you want to get some tube sound somewhere in your system but don't want to mess with the hassle of a tubed output stage. Theoretically, using tubes for voltage gain on the input stage(s) and semiconductors for current gain on the output stage, is the best application for both, although it doesn't always result in the best sound. As another poster above put it, if your speakers are not too difficult a load, you will most likely keep some aspects of the tube sound (warmth, fullness, dimensionality of the soundstage and instruments, liquidity) and some of solid-state sound (quickness, detail, bandwidth, bass impact). I myself have a tubed phono stage and preamp with a SS power amp, and I seem to get some of both. Although these days the line between tubed and solid-state equipment is becoming more blurred. I had Conrad-Johnson and Audio Research tube gear using 6H30 input and driver tubes with advanced output transformers that resulted in a more neutral sound, which to my ears is preferable to the traditional slow and warm tube sound and bright and flat solid-state sound once the norm.
