sorry , i am trying to understand if the resistor introduces THD into the signal path and how. not noise.
yes the idea is to make a low frequency cut adjustable from 40khz -> 200khz or maybe higher..
yes I am looking at datasheets of various digipots ( resistor ladders ) and the THD they introduce.
I understand the impedance seen at the input would add to R1 to modify the RC filter.
can I add the RC in between preamp stages to work around that?
my question is , does R1 introduce harmonic distortion to hot and cold signal path and how to calculate?
What do I need to know about the resistor in order to make the calculation?
How is the resistor distorting the signal?
the input would be from a microphone so in the +/-mV range
impedance of the microphone say 100ohm?
the preamp input impedance is 9.2K
preamp Output Resistive Loading 600ohm
my attempt at drawing with a mouse was not great.. next time i'll try a pen!