The Dalis demand a lot of power to control the bass. I'd be concerned about a tube amp having the desired muscle unless you spend big, big bucks.
I've heard them with about five different amps and the bass didn't really clean up until we got to around 200 watts into 8 ohms. The CJ CA200 mentioned earlier is one of the amps that it sounded pretty good with. It sounded even better with a couple of 500 watt amps (Rowlands). With a 100 wpc Primare the bass was loose and bloated.
Those speakers really need a few hundred hours to break in. The ribbon tweeter can be very unforgiving of less than stellar sources, etc. I'm afraid that when you opted for those speakers you upped the anti on the rest of your system.
Dave