Its this one,ecxept the cathode resistors are now 182 ohms.
Is that first cathode resistor 182 Ohm? Because that first stage is then on 1.7 mA only.
When I am running your diagram in LTspice and doing an analysis I get DC voltage at the common point cathode top tube and plate bottom tube of the 6N6 triodes around 59.5V which I find low. Isn't it better to get there around halve the supply voltage. (=280V)?
But perhaps I do not have the correct 6N6 models.
But perhaps I do not have the correct 6N6 models.
Do you have a model for ECC99 wich I use?But perhaps I do not have the correct 6N6 models.
I use 182 ohm for R1 now. Well sommething changes when I change the tubes. (sound)
Well I am now a little bit puzzled here about the actual resistor values 182 Ohm, 82 Ohm 100 Ohm?
Is it possible to post the actual resistor values of all resistors which are now "in the hardware"?
And perhaps someone can shed some light here about that global feedback. It is connected from the output to the grid at the input tube, which has a series resistor of 100k.
Then in the simulation there is that voltage source, but in practice it will be an input volume control resistor.
Isn't then the amount of global feedback depending on that volume control actual resistor value to earth?
I am using this schema except the cathode resistor 182 ohm.And Ecc99.... And then 6N2P as input tubeIs it possible to post the actual resistor values of all resistors which are now "in the hardware"?
And I use a 1ooK potentiometer.
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When I am running a DC analysis my DC values differ from yours significantly.
For instance the plate voltage of U3 = 83 V in my analysis and around 122V in yours. Same for the output voltage:
mine: 89V, yours: 124V.
I am using 5751 and 6N6P both Ayumi Nakabayashi models.
plate current U3=1.64mA and plate current U1=17.7 mA.
both in my LTspice circuit.
Circuit components are now the same as yours.
For instance the plate voltage of U3 = 83 V in my analysis and around 122V in yours. Same for the output voltage:
mine: 89V, yours: 124V.
I am using 5751 and 6N6P both Ayumi Nakabayashi models.
plate current U3=1.64mA and plate current U1=17.7 mA.
both in my LTspice circuit.
Circuit components are now the same as yours.
Yes I will make it 100 ohms.I would stick to 82 - 100R as it sets the current in the output and hence what you can drive.
A 12ax7 is fine for the first stage.
I use the ECC99 as first stage. A very fine tube.
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