And that’s not a bad thing at all.
"Warm-ish/slightly laid back, smooth but with lots of power/control" would be how I would categorize the sound.
I’ve also had HK before and I would categorize their sound as more forward, more emphasized, especially in the upper midrange and treble. HK’s sound is not bad, but it lacks the control and punch of the Luxman, imo.
I imagine your Tannoy’s would appreciate the power and control a Luxman brings to the table. To me, that sounds like a great match, but of course, your tastes might be different than mine.