That depends on what capacitance is after the 100k balance. But draw your vol pot + bal pot circuit.
If you are using zero ohms for half the balance pot you will find that the vol pot will determine most of the source impedance when the balance is at mid position.
The impedances of the pots and Receiver determine the proportion of voltage that reaches the receiver. It's the filter (capacitances) that determine where the HF roll-off begins.
If you are using zero ohms for half the balance pot you will find that the vol pot will determine most of the source impedance when the balance is at mid position.
The impedances of the pots and Receiver determine the proportion of voltage that reaches the receiver. It's the filter (capacitances) that determine where the HF roll-off begins.
Thank you, Andrew. I am planning on putting together an ST-35 clone (with David G's improved bias). So I think I have to calculate the Miller effect of the input triode to figure out the impedances. In that the impedance will vary with frequency, am I correct that I want to calculate the voltage loss at a couple of frequencies to try to get the signal as linear as I can? Or am I missing the boat here?
the input of the amplifier or any receiver is usually a resistance in parallel to a capacitance.
That capacitance has a varying impedance that is dependent on frequency.
That capacitance also acts as a filter by interacting with the source impedance.
One can add some extra capacitance at the input to create another filter.
You usually aim for a total roll-off that does not remove any of the treble content of the audio signal.
That capacitance has a varying impedance that is dependent on frequency.
That capacitance also acts as a filter by interacting with the source impedance.
One can add some extra capacitance at the input to create another filter.
You usually aim for a total roll-off that does not remove any of the treble content of the audio signal.
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