Tube Pre/ Class D Amp - Who has done it?

Currently, as an experiment, I’ve been using a music hall 25.2 hybrid headphone amp/pre with two NAD 268 amps that are bridged (300 watts/channel). I think it sounds fantastic. It did not cost me a ton of dough, as I got deals on them. I am partial to my sugden class A and my musical fidelity class AB, but I’m telling you, this combo just works. I got the idea from the rogue sphinx which combines class D topology with tubed pre section. I think they are/were on to something. What prompted me to do this was I did not think my other amps provided the oomph I needed when I wanted to rock out with say AC/DC, zeppelin, etc. I can tell you that I’m no longer wanting for that oomph or volume with the aforementioned combo, bizarre as it may be. The MH 25.2 is a hidden gem of a component when used as the pre. My next test is to sub in my passive pre, combined with the NAD"s. For class D, the NAD 268, to me, sounds warm and detailed with no grating harshness. I was surprised, and it has changed my mind about class D. I use the Tannoy eatons biwired. They are fairly sensitive and also add some warmth to the sound, which I’m sure the MH 25.2 is also adding with its tubes. I’m also using, with the NAD’s, the music hall A3 tubed phone stage, equipped with a volume control. That too sounds great. ASR reviewed the NAD 268, and gave it a very favorable review. Other than that, not much fanfare from other reviewers. Some here may look upon these components as total sh#t, I don’t care, I took a gamble on them and I’m loving it. So Tonight That I Might See by Mazzy Star has never sounded so good! Totally enveloped by the music.

Class d is comming of age the fosi audio monoblock is a bargain you can change the op amp to what you want sound wise.i do like d sonic,who doesn't like 2 kw into 4 ohms Dennis is fun to talk to.enjoy the music

Really happy to see all the on-topic replies here. Especially happy that this discussion has stayed focused on the union of tube and Class D as opposed to a free-for-all discussion about Class D vs whatever you like better.

Those discussions are already plentiful in A’gon.

I ask this question in part because I'm about to go fully active in my main system and wanted to know what kinds of combinations had great synergy, but  also because I've always suspected that a juicy tube pre with a solid performing Class D would be heavenly.

I used to run Orchard Audio Ultra DMC Stereo & Monoblocks with a BAT VK50-SE for many years. But recently, I've moved onto the Black Ice Aries/DAC/Preamp driving the Ultra's. Sometimes I'll direct drive the Ultras with my PS Audio DirectStream DAC Sr. (MK1). It's fun when you have options.

The Orchard Amps are a "straight wire with gain" philosophy which will then tell you how good or bad your source is. 

Gato dia 400s.