Tube Vs. SS Preamps

As others have described above, I find tube to offer sound with better texture, saturated harmonics and a presentation that seems to bloom naturally into the listening space.  I think good solid state can sound smooth, natural and lacking in artificial edginess, but, I tend to find something missing that makes the sound seem flat and less engaging.  I own a pretty decent solid state linestage (Levinson No. 32) but, I prefer my custom-built tube linestage (310 tube).  

While you may get a "taste" of tube sound with a tube linestage, I think the electronic component that has the biggest impact is the amplifier.  The right tube amplifier will make a huge difference (the wrong one likewise will sound quite bad).  It is harder to find the amp that will mate well with a particular speaker than it is to match any other components, but,  that is, to me, the big step in improving one's system.

One more thing worth mentioning--some tube linestages do not play well with some solid state amps even when the output impedance of the linestage is low enough that the two should be electrically compatible.  I don't know why that is the case, but, on several occasions, I found this to be true.  The "bad" sound is an overly warm and muddled sound that is also dynamically constricted (the so-called tube sound on steroids).  It might also just be the case that tube linestages, as is the case with all tube gear, vary much more in sound than do top solid state gear which tends to sound much more uniform.  A trial is before purchase is highly recommended for all gear, and it is particularly required for tube gear.