http://geek.scorpiorising.ca/GeeK_ZonE/

This is a small forum made up of some of the world experts on tubes and tube amps. It is a great place to browse and lurk, but I would caution you to think long and hard before joining. Frankly, it is a rather close community of only about a dozen, at best, regular contributors, and these guys are perfectly happy having their own little forum and staying within their own paradigms.

This forum has a big plus: you don't have to join to see the links, attachments or posted photos. Which is good, because you should lurk on this one, maybe for a long time.

The biggest problem I have with this forum is that a few of the members - some of them - are not hesitant about insulting you if your post is in opposition to their personal dogma. I mean being downright offensive. So, you ask for help here at your peril. Maybe you get help, maybe you get insulted. They also like to hijack threads - that is, of newbies. This is an especially offensive practice of purposefully going off-topic to wreck whatever thread you're trying to create. Finally, the moderator, while a nice guy and a tube amp expert in his own way, is more concerned with being "one of the guys" than policing the forum, (he said so himself: here's the link: http://geek.scorpiorising.ca/GeeK_ZonE/index.php?topic=3779.0..)...so he is slow to intervene to stop insults, and, what is worse, he does not delete insults. So the insults stay there forever. Not a good place for beginners to post questions, frankly, but a very good forum for learning by lurking and then looking stuff up on google (or a list of links I'm going to create that get you to articles that explain tube electronics really well). It might be a good forum for someone already expert, who can hold their own in a flame-war...if you really want to subject yourself to that. The members who are especially expert, and professional in their conduct, and whose threads you might wish to read - to really learn some stuff, let me tell you - are:

1. Miles Prower. This guy knows tube amps, topologies, screen supplies on pentodes, power supplies, how to use negative feedback, and he knows how to make tubes WORK. He's also a solid contributor who does not insult, and gives outstanding advice and technical explanations. I have great admiration for his expertise, meticulous thinking and professional conduct. Here are some of his threads and projects that are simply superb, some of the world's best (although he does require you to do your own dimensioning (resistor and capacitor values, for example...but, hey, there's no better way to learn than to take a great design and dimension it yourself - what matters is you've been given a great topology by an expert, learning how to dimension it will make you a far better DIY'er:

Miles Prower Thread: The Wolverine: GREAT 845 SET PROJECT: I AM GOING TO BUILD THIS ONE!!! - THIS IS THE BEST 845 TOPOLOGY I'VE SEEN EVER, AND, WHILE IT'S TECHNICALLY DEMANDING AND YOU MUST CREATE A NEGATIVE RAIL, I'LL BET THERE'S A MILLION WAYS TO TWEAK THIS AMP TO GET PERFECTION:
 http://geek.scorpiorising.ca/GeeK_ZonE/index.php?topic=3866.0

Schematic for the Wolverine: http://img81.imageshack.us/img81/8586/wolverinemainqw0.jpg

Miles Prower Thread: Le Renard: SUPERB 6BQ6GTB PUSH-PULL OUTPUT, SMALLER AMP, DESIGN PRINCIPLES SIMPLY OUTSTANDING, INCLUDING INPUT HEDGE SPLITTER AND IMPECCABLE SCREEN POWER SUPPLY:
http://geek.scorpiorising.ca/GeeK_ZonE/index.php?topic=3492.0

(more to come)

Best, Charlie