6C33C-B. PP or SE ?

[Predator864]

I own 6 6C33C-B tubes.
I intend making me a great sound amplifier.

But the question is :

It will be PP or SE ?

Yesterday I saw this schematic :

http://www.bonavolta.ch/hobby/en/audio/6c33c_3.htm

[inertial]

Hi,

That schematic is by italian master Bartolomeo Aloia
I understand just a little about electronic but it is a high performance-monotriode!
30W ! and good damping factor also !

Cheers,
Paolo

[korneluk]

Consider going single ended, and most important of all, choose cathode bias. The 6C33 has a tendency to drift when operated in fixed bias and run away with cherry-red plates.

Another recommendation is the operating point: 200V @ 200mA is conservative, but sounds good and provides trouble free operation.

Here some reference cathode bias designs:

http://www.borbelyaudio.com/adobe/15wse.pdf

http://www.metaleater.narod.ru/6c33c.gif

Enjoy,

-- jose k.

[korneluk]

And here is the simplest design with all the part values worked out for you:

http://www.mi.ru/~tube-art/6c33_amplifiers.htm

If you're starting from scratch I would try this one or the Borbely design.



-- jose k.

[Predator864]

Thank you guys !

I saw yesterday the Borbely design after some searches.

Found this schematic in a romanian electronics forum:

[tubetvr]

That schematic is very close to an early one by San-Ei in Japan, San_Ei was owned by Dakesue who was the one in Japan who "discovered" 6C33C in Japan and imported this tube and sold it as EC33C. The only differences I can find is that San-Ei used a 12BH7 as the 2nd tube and used local feedback to the cathode of the SRPP, see here http://www.tubetvr.com/se.html

I have one of these amplifiers myself and it gives a very nice sound.

As is evident the amplifier used fixed bias to the output tube and I can vouch for that the output tube current is very stable, it usually doesn't drift even over a year. IMHO 6C33C tubes that are burned in correctly and is not used with more than ~40W anode dissipation doesn't drift.

Regards Hans

[Predator864]

Originally posted by tubetvr
That schematic is very close to an early one by San-Ei in Japan, San_Ei was owned by Dakesue who was the one in Japan who "discovered" 6C33C in Japan and imported this tube and sold it as EC33C. The only differences I can find is that San-Ei used a 12BH7 as the 2nd tube and used local feedback to the cathode of the SRPP, see here http://www.tubetvr.com/se.html


Regards Hans

You must be talking about this :

http://www.bonavolta.ch/hobby/en/audio/6c33c_5.htm

[tubetvr]

You must be talking about this :
http://www.bonavolta.ch/hobby/en/audio/6c33c_5.htm

Yes, as you can see it is identical to the circuit on my homepage

The schematic on the Bonavolta homepage is scanned directly from the original schematic from San-Ei that I have.

Regards Hans

[Akita]

Anyone have the datasheet for this 6c33c tube

[korneluk]

Originally posted by Akita
Anyone have the datasheet for this 6c33c tube

http://www.jogis-roehrenbude.de/Russ...atasheetMB.pdf

http://lib.store.yahoo.net/lib/thetu...e/RU-6C33C.pdf