829B/3E29 "Triode" Push Pull Paralleled Sections

[alexg]

I build 829B PP by shematic.
Sound very good use OPT 10K

Are you using two 829B per channel (paralleled)?

Thanks.

 

[Cassiel]

I'm not a big fan of LTP.

Good to hear. Sometimes I feel lonely here, everybody seems to be riding the LTP train.

1: Use the 829B along with any other "funky" tubes (going for a "steampunk" theme. Brass, Black Wrinkle finish, Antique look)

Nice. Folks, futuristic looking amps are for the transistor guys. I have some 60 years old tubes which NEED a proper environment. Besides, mixing styles produces pain in the eye.

 

[audiodesign]

Someone have time to develop the pcb for my new driver stage ?

PP2011 - Hi-End Push Pull Amplifier

like my

PP2010 - Hi-End Push Pull Amplifier

I can give you the Eagle of the 2010 to modify

 

[audiodesign]

I see in the datasheet of 829B that the max G2 is only 225V.

In the schematic you use higer voltage, no problems ?

 

[Wavebourn]

I see in the datasheet of 829B that the max G2 is only 225V.

In the schematic you use higer voltage, no problems ?

Max G2 voltage is specified for pentode mode. In triode mode G2 voltage can't be way above anode voltage, so it don't apply. Think in terms of max G2 power dissipation instead.

 

[45]

Someone have time to develop the pcb for my new driver stage ?

PP2011 - Hi-End Push Pull Amplifier

Why don't you put the RC coupling between the input voltage-amp/splitter and the pentode section? I see you are using fixed bias. In that case you just need to set up a voltage doubler from the 120V bias secondary in order to get a dual supply and make the cathode negative and at the right bias voltage for the output tube.

45

 

[k9swc]

Why parallel the sections? Why not use each section as one half of the P-P circuit? True, the screens are tied together, but unless you're trying to run UL, they're essentially tied together anyway (my 807 P-P screens are fed through a 100R resistor, but that's effectively tied together.) Also, the internal screen-cathode bypass cap is small enough to be ignored at audio frequencies.

I built an adapter for my Standel 25L15 clone that plugs into the two 807 sockets and provides a socket for a single 829B. Looks cool (different!) and sounds the same as the pair of 807s while only drawing half the filament current ... and thus runs cooler.

Bud