czech tube amp

JJ as well, but pretty sure it was KR I'm thinking of.

That is JJ Electronics........sorry for the typo!

Try JJ electonics. This is the old Tesla brand and they make some sexy amps!

it's KR.

http://www.soundclub.pl/en/producenci/KR-Audio/38.html

http://www.nytimes.com/2003/06/30/business/worldbusiness/30iht-btend30_ed3_.html

http://www.smh.com.au/digital-life/hometech/warm-up-for-heritage-hifi-20111018-1m6p9.html

KR audio makes some of their own tubes & if I remember correctly at least one of the tube designs was unique to them,

nope.  they made their own tubes as well on old russian gear but were rolling new tubes, based on the info on their site.
I thought it might be these guys
http://www.kraudio.com
but the page didn't ring a bell as there was reference to the about page to the tube designer at the company, but perhaps their page has changed in the interim few weeks.