Tube preamp vs Tube cd player

Lots of excellent responses have been provided above, and in particular I'll third ZD's well stated points.

Also, regarding this statement in the OP...

for power amp, most people prefer solid state...

... a major reason for that is simply the fact that more often than not speakers are designed with the expectation that they will be used with solid state amplifiers. In many of those cases using a tube amplifier would result in some combination of tonal imbalances due to non-optimal impedance matching, inadequate bass damping, or inadequate drive capability. Also, a given number of tube watts generally tends to cost more than the same number of solid state watts, for a given level of quality.

But there are nevertheless many speakers that are best used with tube amps. And there are also many that are well suited for use with either kind of amp, with the resulting sonics depending on the intrinsic sonic character of the amp and the speakers, but not on factors involving interactions between them.

If a speaker has above average efficiency and sensitivity, and an impedance curve that does not dip down to low values (e.g. less than say 5 ohms or so) at any frequency, and an impedance curve that does not vary a great deal as a function of frequency, the likelihood that it will be a good match for a tube amp is increased.

Also, regarding matching a tube preamp with a solid state power amp, or a tube CD player with a solid state preamp, you want to be particularly careful to check that impedances are compatible. See my post in this thread for further explanation.

Regards,
-- Al