Besides the two obvious ones (the three hole plates and the date codes) the things I look for are the bottom getter and the rectangular micas with the three 'teeth' on the top mica. There are some other characteristics but this pretty much narrows it down. I haven't heard every 6sn7 tubes so I'm sure there are some that best this, but its still one of my favorites. It may not have the huge low end of the ken rad, but I found it overall a bit more musical and balanced. If you got one under $70 then it was quite a steal!
As far as some of the power tubes (Bendix 6080 for example), they've been getting rarer and rarer. There hasn't been a Bendix for sale on hifishark in over 2 weeks.
As far as some of the power tubes (Bendix 6080 for example), they've been getting rarer and rarer. There hasn't been a Bendix for sale on hifishark in over 2 weeks.