Aikido Heater PSU help

[Bengali]

No, they will handle 300v on the plate directly (i.e 300v directly across the tube from plate to cathode), which means your B+ can be much higher. I have seen designs with 6N1P and B+ of close to 400v, it's all a matter of getting the right resistor values to suit the current you want through the tube. The resistor can be on the plate end or the cathode end of the tube, or in the Aikido series-tube configuration, a mixture of both.
What I meant about distortion in a sub-300v B+ stage is this:
Generally, in a plate loaded circuit (the Aikido is not quite that simple) a higher B+ makes it easier to achieve low distortion, and as the 6N1P likes more than 5mA of quiescent plate current, high B+ and suitable plate resistors are the best choice. Once you get down to B+ around 250v, the 6N1P starts to run out of room to maneuver and the distortion goes up (not enough voltage left across the tube == non-linearity and clipping).
Take a hypothetical example: with 400v B+ and 5mA, you want to drop say 150v to put the plate voltage in a safe but not too low area, which means a resistor of 30k.
The 6CG7 may only prefer say 3mA, which means a different resistor value.
Those were just examples, I haven't actually done the math for 6CG7.
Generally speaking, if the quiescent voltage and current conditions are the same between tubes, the resistors will be the same too. The actual values chosen are done so according to the plate characteristic data of each type of tube, found from the tube data sheets.
The Aikido 9-pin documentation I have shows a big chart of suitable tubes, and methods of calculating critical resistor values for them. Ah, just looked at the all-in-one docs and it is on page 16. There are some other charts in there as well, but I haven't read it all yet.

ah, thanks for clarifying. the 6N1P spec I was looking at stated max 250v for the anode voltage. so for 6N1P, higher +B may increase sound quality.

I'll stick with the +260V for now. I believe mine is running at 5mA.
I'm using 300ohms resistors. will have to double check.

 

[rotaspec]

Looking at my manual (which has some example currents and resistor values), you will have 10mA with a cathode resistor value of 300 ohms.

As your manual doesn't seem to have the headphone output section, go here:
Aikido 9-Pin Stereo PCB

scroll to the bottom and download the pdf, the headphone section is page 8. It shows a method of making it switchable between headphone and line out also.
Note the caveat about tube choice. You need a tube that can deliver a bit of juice. The 6N1P is a better choice for this than the 6CG7 (higher gm)