help on tubes

the tube forum at audio asylum has a lot of great info

Hi T:

Welcome to tubes! Very early in the a.m. here. I'm on the "Insomnia express", so excuse me if I babble.

I can't tell you much about your BAT (never owned one) except that I believe it uses 6C33CB for a power tube --a big power triode used in high-end amplifiers. Made in Russia by Ulyanov. I do not think there are many substitutions for it. It's commonly used in OTLs (amps without output transformers) and scopes in MiG fighters. A good site for russian tubes is www.tubes.ru.
If you go to www.tubes.ru/techinfo/ControlTubes/6c33c.html (case sensitive) you will find all of the specs for those tubes including plate curves. You might not really know what a plate curve is at this point but it is about the most useful info about a tube circuit there is and it may be helpful at a latter date.

I won't make any recomendations on tubes but here are some general intros on tubes so you can "read and learn about the differences of tubes". Ultimately you have to listen for yourself. You might not be interested in Ray's. The first three are easy reads. The sites on tube data at 5 require a little background but not much.

1. “A Taste of Tubes” a nice overview, about 50 pages, of the history of tubes and how tubes work from the folks at Sonic frontiers.
www.anthemav.com/frames/tubes2fr.html

2. “The Cool Sound of Tubes”: Very short overview of tubes. www.spectrum.ieee.org/select/0898/tube.html

3. “How A Vacuum Tube Works” at the Svetlana Site. Very short overview of tubes. www.svetlana.com/docs/tubeworks.html. There is a lot of good information at this site too.

4. Rays Electronics. www.electronicstheory.com/html/e101-37.htm Just a little more involved on the electrical side but very short. This link takes you to page 37 which deals with how tubes work. If you back up to page 1 it is a nice easy intro into the basics of electricity in about 30 pages, followed by about 10 pages on tube electronics, and even a few pages on how a tube fits into a basic circuit. If anyone has a better beginner’s electricity/tube electronics site on line please let me know.

5. Comparing tubes. If you have a question about a particular tube like “can I replace one kind of tube with another”, here are a few sites that will tell you. 1) “Frank’s Tube Data Page” http://frank.nostalgiaair.org/index.html 2) Duncan Amps “Tube Data Sheet Locator”: http://213.123.250.245/cgi-bin/tdsl3.exe 3) Triode Electronics “Tube Data Sheets”: www.triodeel.com/tubedata.htm . Triode Electronics is another good general site. There is some good stuff in the “Dusty Files” section of their tube section which is linked at the top of the page given above.

Well, this might not have helped you much but at least it has put me to sleep. Thanks! Enjoy your new amp.

I remain,

One of the very best sources of tube information is at www.audioasylum.com. They have a whole section devoted just to tubes. You can do a "search" for whatever you would like to learn. Many extremely knowledgeable and very nice people hang out there.

wholly Cow.. i did a search on this tube (6C33CB) on this classified and found that it cost 14$/tube..doesnt sound bad at all,but the original amp owner told me that it cost $160/each.. so,can some 1 help me to see which figure is correct? and where can i buy these russian tube in the U.S?is there a substitution version? and what kind of sacrafice do i take if i replace them with the substituion..thanks for helpping me out

Tube prices can vary widely depending on vintage.
Older Western-made tubes fetch the highest prices.
Chinese, Yugoslav, and Russian current production tubes are the cheapest.

KP