Who are the most underground high-end companies


When I say underground I am talking about companies that fly below the radar. Not much talk about them on audio forums, little if no reviews, no formal advertising, rarely see their gear at shows.

taters
Those companies fly under the radar like Taylor Swift flies under the radar in the pop world.


Many very high-end Euro brands fly under the American radar but not so much in Canada.
Audio brand  obscurity is predominantly myopic on this side of the pond 

these include, inter Alia:

LFD
CROFT
JMR (Jean Marie Reynaud) speakers 
DENSEN
DIAVALET
AUDIO NOTE
ELAC speakers 
Electrocampionet
Audiomat
YBA

and on and on ....