Yep, @Gravitas just buying one of these inspired me to check if there was an official thread. And NO! There wasn’t. There is now!
I also picked up one of these recently. To the best of my knowledge it is still an in-production model, so I will post a full review in this space in the near future.
For now, try to guess whether this is a photo of the engine room of the spaceship of an old sci-fi movie or a shot inside the porthole of a Cayin HA-1A MK 2 tube amp:
(It’s the Cayin 
)
Yesssssssssssssssssss. I think I might do the same if I’m not stepping on any toes. You’ve inspired me.
It’s like five warp cores all working in concert.
Create an official thread? I don’t think you can! 
Do a review? YES! The more the merrier! No toes stepped upon!
@Gravitas asked this:
The switch goes as low as 8 Ohms, actually.
The output impedance selector has 5 settings: 8-32 Ohms, 33-64 Ohms, 65-150 Ohms, 151-300 Ohms, 600 Ohms. The different options do impact the sound, and I haven’t had enough time to play with all the combinations yet.
Man I can’t wait to get this. This is gonna be so much fun.
I sort of wish that I had a use case for this amp because it just looks so robust and also elegant but alas, none of my current phones or those on my immediate wish list are optimal candidates.
For now though, I will be happy to live vicariously through your experiences!
Congratz & Enjoy 
I’m not a “tube guy” for headphone amps mostly because of practical and financial reasons. But I am a spaceship guy in my imagination. And that’s a pretty sexy amp.
Lol. The inside does look like the engine room of an imaginary spaceship! Thanks to you and @Gravitas for validating my weirdness on that! 
I am also thinking about an additional tube amp that will be connected to the Singxer Sda 2.
The Cayin probably wouldn’t be bad either.
And probably good in this price range.
What annoys me is that now that I have soldered all the headphones with a 4 bin Xlr plug, I don’t want to go back to 6.3.
And if I find an amp that fits into the headphones, it will have a 6.3 connector.
I would even like the Cayhin, there is another one from Vincent that is supposedly the same as the Cayhin.
I almost bought this amp last spring but I chickened out due to QC fears.
Right now there is a pretty affordable one on CAM and I can’t help but think, “Man, that is one sexy looking amp”. 
You could get a cable/adapter to convert xlr to 6.35mm, that’s what I do with my Atticus cable to use it single ended as I don’t have a balanced desktop amp.
Adapting 4-pin XLR from the headphone side to 6.3mm TRS is easy.
Yes would be a possibility.
I’ll have to see if I can find it in Germany.
I mean, I still have a 6.3 Furutech plug and a 4-wire cable here.
I would only have to have the counterpart of my 4 XLR plug and solder both minus cables from the XLR to the 6.3 mm plug, did I understand that correctly?
I have See this are the New Model,is it good?
Just like that, yes.
Isn’t it the same with a different name ?
Must be the new one.
It is based on the Mk 1 and 2.
I suspect that the new one has more steam and probably different tubes.
Unfortunately, there are hardly any tests, reports or the like, which makes things really difficult.
I don’t know yet if I should dare to buy it.
It seems to be reasonable.
Everything else I’ve seen so far that would be a bit cheaper is based on hybrid or much more tube rolling.
I’m not too keen on that.
I could also get Cayin Cs 1h in Europe.
I think I’ll wait and see what Wavetheory has to say about his and then decide.
I think his model and the new one won’t be too far apart.
Mk1 was a speaker amp as well. Mk2 cut the speaker taps and made some internals improvements, I believe, which improved the performance for headphones.
I googled it and i found nothing but germans links. It could be exclusive to you guys? To me it looks exactly the same as HA-1A MK2, it has the same specs as far as i can see except for the power, 100mW less at 32 and 600ohms. Tubes types seems the same but they could use different ones than HA-1A MK2.
Did you check Tor Audio and Feliks amps ?
I’ve been looking at the Cayin for a while but a few concerns put me off. Resolve also told me it’s super sensitive to vibration. It would be nice if @WaveTheory or anyone else could do some quick testings about that.
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