I was wondering what the best possible (within reason economically that is) measured performance of a tube preamp would be. I dont think my hearing is all that great for distinguishing higher resolution versus cd standard sound quality, so not only am I not looking for the impossible, but I doubt I would know it from the reasonably possible. I have seen in comments on this site that amplification with valves introduces more artifacts/noise/distortion than using tubes for line level applications. I know this is forbidden territory for a lot of objectivists on the site, but I still wonder about the best possible scenario of mating a highly resolving solid state/digital amp with very low measured distortion mated with some of the best tube driven pre amp for certain music listening. I always enjoyed tubes on acoustic and natural instruments, but obviously they have their draw backs. Anyone if know if there are tube pre amps that actually reach full 16 bit cd resolution or better? Which models if so?