Cayin A 300B

You're welcome. 
By the way, I found the comment from the user toro3, here in Audiogon, regarding tube rolling.

Looking at his KA-101 I saw a different rectifier tube. When I asked about it, this was his answer:
"...that’s the smooth black plate RCA 5U4G with round mica at top and lower d getter. I prefer the 5U4G over 5AR4 and 5U4GB due to sounding richer IMO".

This user, toro3, has a system similar to mine: Kingko amplifier and Omega speakers. You can find his system and comments here at "Virtual Systems".

Any idea if it can take a 274b? I have a couple of those as well as several 5u4 types. My speakers are very efficient Klipsch so the low wattage from the Kingko is appealing. 

I asked King Ip about that. His answer is Yes, you can use those tubes (274B and 5U4).

If we could, try to bring this thread back to focus on CAYIN’s new line of amps,
Especially, if not specifically, lets highlight the 3
845 amps offered by Cayin. I have my eye set on the $2800 model, which I may try to purchase mid 2020.
IMHO, the 845 tube, which i’ve not heard personally, is the King and Queen of all tube amplification, making it the most musical of any /all amps, (I am not a believer in solid state amps, I in fact despise SS amplification = strong disgust of SS amps).
https://vasnyinc.com/cs845a/

Cayin needs to establish a  EXCELLENT storefront here in the USA,,with shops set up in major cities with 1 tech guy avaliable for repairs, and auditions.
having the worlds best, most musical amps, w/o a  distribution network, is not doing any justice to the many who would love to own a  cayin amp.
IMHO, it will be the 845 amp which wlll  bedome the world's #1 most desirable amplification. 
sadly Jadis can't match that. 
Also jadis has no repair centers avaliable locally, To repair a  Jadis amp, one must send it to California at a  ship cost of ,,,~~~$300~~~, 
Completely totally ~~~rediculous~~~. 
I'd never buy another Jadis ever in my life. 
For me there is only 1 amp to own, the Cayin CS845,,and get this I've never heard the Cayin nor any 845 tube as yet.
Paul
The honest stereo review  critic, 
New Orleans