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6C33C tubes - sonics, implementation & availability

Just looking for thoughts on the 6C33C tube and amplifiers using the 6C33C tubes. I know BAT, Lamm, Audio Mirror, Tube Guru, Wall Audio and others use this triode tube in differing topologies....some SET, some PSE and others push pull.  How does this tube compare with the 300B sonically?
Is there a preferred topology for this tube considering the higher current and from what I've read tube to tube variability/instability? I've also read these tubes are no longer in production but there are fairly large stockpiles, but many unreliable. Looking at the Wall Audio PSE M50 Monoblocks myself.  Thanks for all opinions!

normie57
normie57 OP
50 posts
 
Thanks, Ralph, for your comprehensive comments!
Forgive me for not including the OTL topology used in your earlier offerings as well as Joule Electra, etc. I wish there was a way of knowing whether individual manufacturers use more heavy duty sockets and wiring. I’ve also read that warming the filament for 3-5 minutes before HT power is applied may prolong tube life.


atmasphere's avatar
atmasphere
11,841 posts
 
There is no such thing as a 'heavy duty socket' for that tube!!

The typical warmup time is about 5 minutes.

We recently reissued the Novacron in an updated version.

Its a popular tube with OTL manufacturers. In fact most OTL manufacturers use it; you don't have to use very many to make power and it also has a low plate resistance.
keithtexas
352 posts
 
Another good source for information is Vlad Bazelkov, maker of Audio Mirror amps that use that tube.  Great guy. 
http://audiomirror.com/
steakster
1,892 posts
 
Excellent info here: "The 6C33C Survival Guide".  My 50w push/pull monoblocks use them.   No need for a space heater in the winter.   I’ve purchased many of these tubes from Russia via Ebay.   The sellers were always trustworthy.   Yet, some tubes were DOA.   I just purchased 50% more than I needed.

Here are photos of it being used in the guidance system of a Russian cruise missile.
atmasphere's avatar
atmasphere
11,841 posts
 
^^ the survival guide is good with one exception; Romy's assessment of the Japanese socket is flat out mistaken! They actually have a shorter life than the ceramic sockets and should be avoided. This is because the 'plastic' he refers to is actually Teflon and is such a good insulator that the pins of the socket actually run much hotter than they do with the ceramic sockets. I have to assume that he never used them or he would know this.
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