With the right value for anode resistor the smoothly non-linear second-order distortion created by the valve characteristic could be partly cancelled by clipping caused by grid current. The result would be low THD, at a particular volume level, but awful sound.
Astonishingly, this technique was actually advocated in an IRE Transactions paper in 1955 by J Z Knapp "Low Distortion Operation of Some Miniature Dual Triodes". I guess back then they didn't know how awful high-order distortion sounds.
Astonishingly, this technique was actually advocated in an IRE Transactions paper in 1955 by J Z Knapp "Low Distortion Operation of Some Miniature Dual Triodes". I guess back then they didn't know how awful high-order distortion sounds.
I searched the web found a 12V 12AU7 headphone design so I think the 50V won't be a problem
DIY 12AU7 (ECC82) Tube - IRF612 MOSFET Hybrid Headphone Amplifier
NP-100v12: DIY 12AU7 (ECC82) Tube / IRF510 MOSFET Headphone Amplifier
DIY 12AU7 (ECC82) Tube - IRF612 MOSFET Hybrid Headphone Amplifier
NP-100v12: DIY 12AU7 (ECC82) Tube / IRF510 MOSFET Headphone Amplifier
I searched the web found a 12V 12AU7 headphone design so I think the 50V won't be a problem
DIY 12AU7 (ECC82) Tube - IRF612 MOSFET Hybrid Headphone Amplifier
NP-100v12: DIY 12AU7 (ECC82) Tube / IRF510 MOSFET Headphone Amplifier
Nope, and I bet it sounds pretty bad..
wooo
a big mistake. grid shold be tite to VSS, not GND
look at this one
should I add a small positive voltage (vs VSS) to grid?
a big mistake. grid shold be tite to VSS, not GND
look at this one
should I add a small positive voltage (vs VSS) to grid?
It also won't like the bias arrangement. Hint: Look at the potential between the grid and cathode - should be a few volts at most. (Need input cap and one more resistor..)
A 6DJ8 would work a lot better here.
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wooo
a big mistake. grid shold be tite to VSS, not GND
look at this one
should I add a small positive voltage (vs VSS) to grid?
No...
I think I should also try with 6N8P(6NS7)
I assume you mean 6SN7 since you reference 6N8P - again not a great choice for low voltage operation.. The 6DJ8 will actually function fairly well with 50V across it, particularly if a CCS or choke is used as the plate load.
As DF96 points out higher voltage operation would be a better choice, and at 200V and above the 6SN7 will work fairly well.
Just for fun.
OK, but don't put it up for sale on your website, some innocent person might take it seriously
OK, but don't put it up for sale on your website, some innocent person might take it seriously
Oh No, I said just for fun, pure personal project...unless it has amazing performance, haha, who knows? Maybe I can send it to a guru for review when it's done. But now I have to learn more about tube. It's a all new domain for a DSP and embedded guy like me. Hope you can help me
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