RC Chain in a 3 Band Baxandall EQ Circuit?

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What is the significance or advantage of incorporating this resistor/capacitor in series in the following 3 band Baxandall circuit? I've also seen similar circuits, but without these two components! The values in this particular circuit are;

R10=270 ohm
C8=1.2nF
 

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Many opamps are unity gain stable.

However, many of these same opamps are not stable for gains <<1, which is the case with the Baxandall at high cut wrt gain.

The network you see raises the loop gain at HF so that the circuit remains stable. The resistor in series with the cap simply inserts a zero so that the HF loop gain limits - otherwise you would get other problems.
 
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Just thinking.....am I correct in assuming that the HF gain would never go down to unity gain or for the the matter < than unity by the sheer nature of the "tone" circuit, hence would always have some gain?

I' ve built a few of these with & without & this in the circuit, but never observed any oscillation or any notisable effects even when all the controls completely turned down!
 
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