If NOS pre or power tubes became unavailable altogether, what new tubes would you buy?

@lewm,
Thanks for clarifying that not all 6SN7 *types* are identical. I was merely trying to assure him that he wouldn't be applying plate voltage to the grids or heaters. Electrical variations (as I mentioned) do vary from tube to tube. Of all the 6SN7 types there's only one to be leery of and that was a mil-spec RCA VT-231 that pulls significantly higher filament current and could stress the x-former tap. 
Yep, it's important to find the tube's idea point on the curve, which depends on your circuitry. I (and the design used in VTA/Tubes-4-Hi-Fi gear like about 45% for the 6SN7s I use but it's not a magic number. I sure wouldn't go much above 65-70% for such a low Mu tube.
If John Bedini could build the "near perfect sounding" amp out of sand components 30 years ago, I am sure there are ss pre-amps and pwr amps out there I'd like better than my tube lash-up. But as you say, most of the new stuff has crap fail-safe circuitry and cheap parts. Even on the tube side a lot of very expensive production gear uses junk. Why McIntosh went with the EH tubes in their driver section I'll never understand, when for a few bucks more . . .
As to s/s vs. tubes, that horse has been beaten to death. Whether tubes or s/s, the sound is going to be far more flavoured by preamp components and the amp's driver section than the honkin' amp, at least according to the all-knowing myself :-), and might be worthy of a thread if there ain't one.
Cheerio,
-d-

Dear @jbhiller : No one has to worry about tube sources because always exist better alternatives that are almost really unknow for many of us and that's why I posted here.

Is clear that many of us want to stay sticky on tube electronics and maybe because many of us already losted the " adventure " esprit of a human been. Looks like many of us already losted the " quest " to find out what to do and how achieve a true better system quality performance level in favor of MUSIC.

Certainly rolling tubes is not a true answer to but try to learn how to look for true answers.

This is what a gentleman posted in other thread :


"""  the most accurate phono cartridges sound more like good digital . This makes me think some people do like pleasant distortion  . Remember ignorance is bliss until you have heard the difference . """


" until you have heard the " true " difference ": we can't have a true valid opinion in what we have not valid experiences.


Regards and enjoy the MUSIC not DISTORTIONS,
R.

My mistake, it has to be this way.

"  we can't have a true valid opinion if we have not valid experiences. "

R.

@rauliruegas 
If you can't identify at least one piece of gear you believe is better than whatever other piece of gear (or better yet, the entire signal path) you've heard, as I have asked you for, then I suggest your opinion reflects the depth of your experience. C'mon, give it a try. I won't flame you. I just want to know what experiences you are basing your opinions on. Perhaps I will learn something.

One thing about Raul is he can make you think . This is a tube rolling thread after all . The question I ask myself if different tubes sound different then maybe he is right . I know it is nice to use tubes to change the flavor to our liking but is it a true accurate representation of the recording ? I don’t think so . We must ask again do we want the truth or the euphoric pleasant distortion ? I too am using tube amps and love the way they sound but I am tempted to try a SS amp I am considering a Benchmark ABH-2 . At least I wont sweat in the summer .