Some of the early SS gear does indeed sound fairly tubey. Probably the output caps like Larry mentioned. I've got a first generation Sherwood solid state, and its surprisingly similar sounding to the Sherwood tube integrated it basically replaced. Even my cap coupled Pioneer has a certain musical sound to it that later direct coupled amps don't really match. DC amps might beat the snot out of a cap amp in terms of accuracy, specs, and damping but I find that they tend to suck some of the life out of the music. Maybe its just the reduction in damping and the wee bit of whatever extra distortion the cap adds to the equation that explains it.