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Originally Posted by tangent  Yes, I'm aware of the high resistor value problem in the Cranky Op-Amps article. I welcome suggestions for alternate configurations that still meet all the requirements. The main thing is low DC offset with high Iib op-amps even accounting for the variable +IN resistance due to the pot. If you leave the pot out, it's easy to get the behavior you want with low resistor values.
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I think this is an elegant way to balance the input currents (R3 could be a resistor and a pot in series):
I'm sorry if the zobel network on the output is confusing. It has nothing to do with balancing the bias currents. It's the JFET on the input that does the job. Since LM6171 is supposed to be cranky, I added it for increased stability with capacitive loads.
A buffer in front of the opamp is another option:
A compromise. I think most sources has low enough output impedance for those values. A drawback is that the input impedance will vary with the volume setting.
