Tube amp / SS pre or SS amp / Tube pre?

Gee Unsound, that describes my system as of last week...
(Well, maybe not the "unlikely but surprisingly" part - and yes, it works fine :-)

I have previously posted the same thing Marakanetz is saying: despite the popularity of the tube preamp/SS amp pairing, I tend to think it's the power amps where placing tubes (power tubes) will give you the most of what tubes do that is distinct from transistors. But considering how fine your current SS system must be (and not understanding your qualifier about where the analog front end winds up) - and considering that what you're talking about is a second system, not a replacement - why not go whole hog if you're curious, and do a totally tubular new rig?

Marakanetz and Zaikesman suggestion of putting solid state pre before tube amps usually offer more opportunties for appropriate impedance matching.

How about a CD player with a tubed output stage? I'm not a fan of SS amp w/tube preamps, too much of a compromise and the worst of each setup is often emphasized, at least in my experience. A good tube CD player can you the magic of each without making so many tradeoffs.

I think the question is a little too simplistic. While the general feedback provided is probably correct, there are many other factors to consider.

Which tube amp would you consider? Alot of tube amps are designed primarily for high efficiency speakers. If you want something to potentially improve on your Levinsons, you may need to change speakers to expand the pool of canidates further than the big ARCs, VTLs, Atma-Spheres, etc.

With a tube preamp, you can get a taste of tubes without worrying about your speakers. As others mentioned, you do need to check compatibility with the amp, but this may not limit you as much.

From a practical standpoint, tubes are more of a hassle then SS (recurring cost, reliability, noise, heat, availability, etc). However, tubes in the preamp seem to have less of these issues, so this may also tilt things for you in favor of trying a tube preamp.

Frankly, since your happy with your SS system now, I wouldn't recommend changing to tubes. There is no guarantee you will be happier just because you now have tubes. I respect what tubes bring to the table and some people's preferences, but "tubes don't always rule." I've always thought that if you can get happy with a state of-the-art SS setup, then why bother changing to tubes. You may notice some benefits, but I bet you also find some tradeoffs too.

There is not a prevailing opinion on SS-Tube combinations. I seen a fair share discussion on this, and what combination prevails is the opposite of what prevailed before. Cases can be made for any combo, but the best combo at the ultimate price, imo, is tubepre w/ tube amp.