• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

6h30p-dr bat vk51se

In my BAT i used to own from 2005 to 2015 i tried every available 6H30 out there and i can confirm that every time 6H6 types sounded way better and more quiet in every respect.
However, i can understand that you all prefer 6h30 types but in the original BAT not only the working point is almost exactly the same, but in my taste they sound way better with 6H6 tubes. What is very annoying with these, is the usual problem with most high gm russian tubes, it is extremely hard to get matching triodes in the same envelop and even harder to get two similar twin triodes which is almost impossible.
 
Miguel,
Have you put at least 50 (preferably 100 or more) hours on the Sovtek 6h30p tubes before judging sound quality?
I agree with Panos, it's hard to get 6H6 that match. Either buy from a reputable vendor or by a bunch, they are not expensive, from Eastern Europe and sort them yourself.

Cheers, S.