Unison Research Aria S2K with Hales Revelation 1 [bookshelf speakers]


I purchased a pair of Hales Revelation One's back in the late 90's and I've had them in storage for quite a while.  I have an opportunity to purchase a Unison Research Aria S2K tube amplifier from a friend.  Does anyone have any knowledge or opinion as to whether this would be a good mating of amp and speaker?  The amp is favorably rated, and many report that you should not be fooled by the low power output; that it drives fairly large speakers very well.  But at 15W pc, will they drive the Hales sufficiently?  The current owner of the Unison amp is driving Nola Viper Reference Loudspeakers (whatever variant was available in 2006 when he purchased them) which are rather large floor towers, and he is quite satisfied with the performance.

Anything you can contribute would be appreciated.  Thanks!

chametzoo
https://www.dhtrob.com/overige/tubefriendly_lsp_en.php

I guess by the lack of response to my original post, it's a rather naive question?  The link above, I found to be a sober assessment of 'tube friendly loud speakers'.  In my searches through the forum, I'm finding that some believe there are unbendable rules regarding pairing tube amplifiers with loud speakers... such as seeking speakers with high sensitivity, etc.  I guess the proof is in the listening and the listening environment.  It's possible, I may be able to take my Hales over to the S2K amp owner's place and see how they sound together.  He's offered me his NOLA Viper speakers as well, but my listening room (the living room of my house) is a gorgeous space and not easy to furnish, so his large NOLA's may not fit in aesthetically... or fit in at all.  Hence, me digging out the smaller Hales from storage.

Originally, when I bought the Hales, I was running them off of a late 70's Marantz 2040 solid state receiver (40W pc).  In the stereo shop's listening room, with their equipment, the Hales sounded great... on the Marantz, they were a disaster.  Sound broke up badly at high volume levels.  I thought, either the Marantz can't drive these speakers, or there's something wrong with the Marantz... at that point it was probably 20 years old and had seen a lot of wear and tear.  I suspect the latter.  I also just looked up the Marantz on line and it had a 4 ohm output, while the Hales are 8 ohm.  Was that a factor?  All of the above?