2H in the output of a PP Amp near max power? Somethings Wrong!👎
Still like to see your Schematic tho. THX
The IMD by the SMPTE method at 3W got left out in the results post.
And the schematic duplicated. Must be getting olde. 😀
Still like to see your Schematic tho. THX
The IMD by the SMPTE method at 3W got left out in the results post.
And the schematic duplicated. Must be getting olde. 😀
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no , 3rd only, and before it saturates, I don't know what you are trying to get at? I don't have a computer version of the schematic and not going to do one. It is a simple floating grid bias input and concertina, it is balanced, 6bl7, the voltage is quite low, bias around 45 ma cant remember, I learned a lot about various versions on the tube, some can't stand bias, some are very resistant. Their internal components are different.
All I can say is that it is not an accurate amp , or a distortion machine, but it has a lush pleasing sound, perfect for small room.
All I can say is that it is not an accurate amp , or a distortion machine, but it has a lush pleasing sound, perfect for small room.
fyi = 18 watts , I guess at 10% , I have similar results, around 14 watts mine is clipping
https://doggenshozen.wordpress.com/2019/06/13/30w-push-pull-e-linear-6bx7-6bl7-amplifier/
What is very consistent is that people love the sound of that forgotten tube, for my own satisfaction it lacks the detail/punch/dynamics and is not accurate sounding, but the bass is nice, and it is very balanced sounding... so the question is the triode able to achieve the clarity of UL if you use a high end output transformer like lundhal and double the tubes (8 in total, 16 sections). ? It is worth pursuing due to the simplicity of the circuit.
https://doggenshozen.wordpress.com/2019/06/13/30w-push-pull-e-linear-6bx7-6bl7-amplifier/
What is very consistent is that people love the sound of that forgotten tube, for my own satisfaction it lacks the detail/punch/dynamics and is not accurate sounding, but the bass is nice, and it is very balanced sounding... so the question is the triode able to achieve the clarity of UL if you use a high end output transformer like lundhal and double the tubes (8 in total, 16 sections). ? It is worth pursuing due to the simplicity of the circuit.
14-15W out of a single 6BX7 is pure class B but requires rather high plate voltage if it were possible, I guess. Close to the 500V limit. Even from parallel PP, 14-15W it's closer to class B than A.
18 watt around 1 % thd is possible with 4 tubes , the question is it worth it when you can have lower cost amps with other types of tubes, what is great of the 6bx7 is low plate impedance etc.
It's not worth it. With 4xPCL82 per channel you make the entire amplifier with ample choice of circuit, having 4 signal triodes as well. The PCL82 triode-strapped pentode is just as linear as the 6BX7 and run at 280V/25mA has about 1.6-1.7K plate resistance. The output power is up to 10W, with 4-5K OPT.
6xPCL82 get to about 15W and one can also have phono preamp with little else added....
I would not do it anyway because I find that pentode +local feedback and in the case of PCL82 even UL with modest loop feedback are more convenient. Zout is relatively low anyway.
6xPCL82 get to about 15W and one can also have phono preamp with little else added....
I would not do it anyway because I find that pentode +local feedback and in the case of PCL82 even UL with modest loop feedback are more convenient. Zout is relatively low anyway.