Tony's 6C33 pp amp build progress....

[TonyTecson]

i am building myself a push pull amp...
OPT is 800 ohm anode to anode, to 2, 2, and 8 ohm speakers
the output tubes topology.....

driver tube will use the 6LU8, the pentode side will be used as cathode followers....

the triode side will be a long tail phase splitter...

i plan on using the 6J9 as input tube.....
more later...

 

[azazello]

Great! /I think 400 ohm for every tube is small load, if You use one tube for a channel/. Or connect 8 ohm speaker to 4 ohm output.
/....very long PP amp, 6SN7 will work good as phase splitter, if You use one tube for channel, 6J9 is good addition to 6SN7.../

 

[needtubes]

I look forward to hearing about your results - the 6C33C has become one of my favorites.

Keep us posted!

 

[TonyTecson]

thanks, i stopped counting the watts a long time ago....
i just wanted a good sounding amp built from the ground up by me....
nothing can give me more satisfaction...

 

[azazello]

Great! /I think 400 ohm for every tube is small load, if You use one tube for a channel/. Or connect 8 ohm speaker to 4 ohm output.
/....very long PP amp, 6SN7 will work good as phase splitter, if You use one tube for channel, 6J9 is good addition to 6SN7.../

Sorry, I have a mistake ........"if You use one tube for a shoulder"...../not channel... in both places/. The tube has Ri about 130-150 and more depends of current, this data is for current about 400-500 ma...if You use in PP small current, Ri will be bigger and 400 ohm per tube /shoulder in PP/, IMO, will be small. /I used OT 1.2 kohm per tube/.Distortions will increase. Tube sounds itself some aggressive and sense of sounding will be, IMO, some discomfort.

 

[TonyTecson]

that is the reason i made the secondaries 2. 4. and 8 ohms, matching then is easy...

 

[azazello]

The choice is Yours.....Go ahead! We waiting for a results..../But my advice is Go to OTL-OCL.../

 

[TonyTecson]

tube complemets....
4 x 6C33
4 x 6LU8
2 x input tubes, very likely an EF80 or a 6J32 or 6J9

 

[TonyTecson]

6C33 preheating and burn-in...

 

[TonyTecson]

chassis preparation....
aluminum, 3 mm thick and measures 20in deep x 14 in.s wide x 3 in height..

 

[donnyab]

where do you get your chassis done ? yourself or a metalworking shop ?

 

[TonyTecson]

where do you get your chassis done ? yourself or a metalworking shop ?

myself....but cutting, bending and forming done by Unity Metals along T.Alonzo St... i keep lots of various sizes of hole saws and drill bits... then off to a powder coating shop...

 

[stajo]

Looking great, will follow this.

What are those manly red/brown caps btw?

 

[TonyTecson]

filter caps....more under the hood...😉

 

[HeyBill]

Mighty fine looking chassis. HeyBill

 

[stajo]

filter caps....more under the hood...😉

Hehe yea so far I understod but what brand/type?

And whats the stuff under the 6C33's cathodes? Biasing chokes?

 

[TonyTecson]

Mighty fine looking chassis. HeyBill

thanks, though made of aluminum, it still is heavy....😉

 

[TonyTecson]

Hehe yea so far I understod but what brand/type?

And whats the stuff under the 6C33's cathodes? Biasing chokes?

posting more pictures soon...

the OPT has a tertiary winding that connects to the cathodes for partial feedback, i am not using global feedback...

 

[TonyTecson]

power traffo and choke....
power traffo is made out of a 1 3/4 inch center leg, stacked to 3 inches and can handle 750 watts...
filter choke is 1 inch center leg stacked to 1 3/4....

 

[TonyTecson]

power traffo powder coated endbells...