non inverting opamp with gain

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Hi. I want to put a non inverting op amp (gain=2) at the output of my crossover (need a bit of gain for LF). Just want to check if my diagram is ok.
Thanks
Pierre
 

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When using a bipolar input opamp, a coupling cap between pot and 1meg (for which 47k will do easily) would be highly recommended. A FET input part should not require this. I would skip the old TL07x in favor of more modern varieties like TLE207x or OPAx134 though. Do use an output isolation resistor near the output pin (but outside the feedback network), 100 ohms or so should do. Something similar may be useful at the noninverting input.

Source impedance of a 20k pot driven by a low-impedance source is 0-5k, so feedback network is best chosen at about 5k/5k for an impedance imbalance of no more than 2.5k (and output loading of 10k, which is OK). The contribution of input impedance distortion to 10 kHz THD should then be limited to about 0.003% at 7.75 Vrms out and is likely to be swamped by other sources. Not like you'd care much in an application like this.
 
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