[Alex Kitic]

Zitat:Original geschrieben von kahlo

Please, write in english. It seem's to be easier for you, possibly easier for us too .

Well, as a matter of fact it is
Point is, the Chinese amp looks like something that could be relatively easily modified to RH88 status (predecessor of the RH Universal) but details are needed (very seriously checked) on the voltages (B+, Ua, Ug2, Uk), biasing method (automatic via cathode resistor?), and the existence of an eventual feedback loop (external loop).
Assuming the driver pentodes are in triode mode, a modification of the basic circuitry is relatively easy, starting from the latest RH Universal v.2 on my blog (will accept almost all common triodes as drivers).
The output tubes are probably pentode/tetrode connected, which means that depending on the Ua-Uk (voltage across the tube) we can determine the maximum possible current draw, and if there is a cathode resistor, either leave it (what for?) or replace it with an LM317 with current setting resistor just like in the Universal.
After the above operation, which does not need many components or too much soldering and building skill, the amp should sound very near a "real" RH Universal (or RH88 if you wish), the difference being in the power supply (you cannot compare cheapo diodes with smallish caps with vacuum tube rectifiers, choke loaded power supplies with large caps...).

I could have translated this with some automatic program, but it would probably sound silly...