pass labs xa30 to valve amplifier.

Have you ever considered a tube preamp or do you want to stay direct from Droplet to amp?

Pubul57,

"I'm thinking there is something about multi-driver speakers that makes a difference in the simple sensitivity/watts equation we normally make"

I've heard/read that complex x/o's eat up power. That and the fact that you have the spectrum of music coming out of poly?/woofers, kevlar?/mids, titanium?/woofers at the same time makes me wonder how I was able to enjoy music out of "those" types in the past. The answer is, my ears didn't know any better.

These days, besides my Maggie 3.6's, I like a good 2 way with a x/o around 2.5K or higher. Trick is getting a mid/woofer to play nice up to and thru that point. I favor soft dome or ribbon tweeters also. Add to that an impedance (nice if it's 8 ohms) that doesn't vary much (say 20%) and it becomes a recipe for pleasure for me.

You Zingalis have the efficiency for not needing many watts (tube or ss) but if they have any severe dips in impedance and even worse, a bad phase angle in the lower ranges, a tube amp may not be the best choice. Most tube amps do not like dishing out a bunch of current at a moments notice, the Pass couldn't care less.

A tube preamp would be a step in the right direction. A tube amp may be a bigger step toward your goal.