Tube recommendations

[20to20]

FYI the curves are here, and the max plate voltage is quoted as 330V not 250V:

You beat me to it by 2 min.

 

[pblix]

So if we assume the tube in question has a 250v design maximum plate voltage, and is being run at 450v. then you could use the 6SN7 curves by shifting right. You would approximate the overvoltages by using the 250/450 ratio of 55%. So lay up your loadline as if the plate voltage on the 6SN7 was 700v.

I disagree with your method. It may be a worthwhile exercise with two similar tubes from the same manufacturer, but even then it's a stretch.

 

[pblix]

I just finished the load-lines for 6N8S from the spec sheet Merlin linked to in his post. I never saved the previous ones I did for 6SN7, but from memory these turned out darn close if not identical. So, my previous conclusions still stands as far as I can tell.

 

[carlthess40]

I have one of those "Nobsound" single ended amps that uses the following tubes:



X2 PSVane KT88's

X2 6N8P Preamp tubes

5Z3PA Rectifier



In general I've been happy with it but have wondered if it could be improved. Are there any drop-in replacement tubs that would give better sound quality? I'm not looking for power (it's a low power amp anyways) as much as clarity and "feel", and I'm using two Sony full height speakers.

It’s funny when someone starts a post to ask a valid question for some information about something and his post turns into a bickering back-and-forth about something that has nothing to do with his question

Just giving my 2cents