Now this is just retarded. You can't introduce even ordered harmonic distortion that tubes have through EQ. Do you even think these things through?
And yes, there has been studies that corraborated that even ordered harmonic distortion is more pleasant to the ears (which tube-amps have a lot) vs odd ordered harmonic distortion (solid states).
Regarding the EQ stuff...There is absolutely NO WAY I can make the Onkyo A-5VL stereo amp sound like the Asus Essence STX soundcard. I've tried but it's just not possible. And they are both solid states. The differences are somewhere else than in the FR.
Just thought I'd point out that while this is true, tube amps tend to have a higher percentage of THD (in the area of 0.1 - 0.2%) and solid states have a much lower percentage (0.005 - 0.01%). This is why many who like that warm sound go for tubes and solid state is attributed more toward "accuracy". So really it just comes down to personal preference and what you are looking to get out of your setup.