• 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.

6Y6 SE amplifier - Definitive project

Yes, it is. And last but not least, the ease of calculations for the right setting.
Another trick to make the circuit even more elastic is to use a 500 ohm potentiometer in series with a 47 ohm resistor on the 6V6 cathode... this gives the possibility, both to power the Screen of other tubes that require a lower voltage (think for example 6CL6, 6W6, etc...), or use other types of tubes instead of 6V6 (for example, if you only have 9 pins sockets, using a 6BQ5, or similar.
Merry Christmas.
View attachment 1122874
 
Excellent suggestion as icing on the Christmas cake !

See below what can be done on a larger scale (valves requiring high voltages).
In my case, I would like to try to build something like this, always sticking to 2 stages (driver and power amp in two separate chassis).
I have a pair of Telefunken EC8020s to use as drivers for everything, even a 211.
The physical separation into two dedicated chassis becomes not only convenient, but also necessary due to the weight and bulk of the components involved.
Usually (even in stratospherically priced commercial designs) they accomplish this by separating the power supply from the actual amplifier and joining them with an umbilical cord where a bunch of wires run that also carry the very high voltages.
No one thinks of doing it like here, where the advantage of letting only the audio signal pass between the two chassis with a common rca connector seems more logical and convenient.
Unless (but I don't see why) in these high-voltage amplifiers, the rca cable connection you have used poses a danger for reasons I cannot fathom.


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A 1K pot is probably better... it must be reliable but not particularly powerful since the voltage and current on the cathode are low... a 1W one is enough. Thus, medium power triodes such as 12B4A can also be used instead of 6V6.
 
There is an error in my calcs, Imax is 128 mA, not 138 mA. Imax is where the curve for G1 at Zero crosses the 2.6K Loadline. The power output is then 4.34 Watts. And 2H is 9.3%.

More power but at greater 2H is possible by rotating the loadline clockwise. Say to 2K. Plate Dissipation is still OK except on program peaks.
HD isn't a fundamental problem if you don't squeeze the amplifier to the maximum levels... at half volume 2H should be around 5% and 3H at 3%... they are acceptable values... on the other hand the beauty of the sound of these tubes also prove it in reality.