Didn’t Prasi already make a layout for you here?
https://www.diyaudio.com/forums/sol...mate-fidelity-amplifier-1066.html#post5542549
You might want to add a resistor (circa 220R to 2k2) in between the main driver amp and each of the slave amps.
I don’t think R11 is needed. R14 could be 47k to 100k.
Most important thing is having low ESR 100nF cap (film or x7r) as close to the power supply pins (between each rail and GND) as possible.
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You don't need the first op amp stage. Simply drive all the parallel op amp stages from the input. The op amp impedance is very high so no problem.
The input impedance is defined by the parallel combination of R11 and R14.
You definitely do need a resistor at R11 - else there's no dc path for the non inverting input.
R14 discharges the input cap to minimise 'pops' on plugging in so you have to balance the time constant against input impedance.
If you drive three op amp stages in parrallel you will have one stage free if using dual opamps as shown.
Suggest to add another output. Or use it to parallel one of the outputs to lower noise.
Also you might consider making the outputs impedance balanced wrt resistance for pennies...
The input impedance is defined by the parallel combination of R11 and R14.
You definitely do need a resistor at R11 - else there's no dc path for the non inverting input.
R14 discharges the input cap to minimise 'pops' on plugging in so you have to balance the time constant against input impedance.
If you drive three op amp stages in parrallel you will have one stage free if using dual opamps as shown.
Suggest to add another output. Or use it to parallel one of the outputs to lower noise.
Also you might consider making the outputs impedance balanced wrt resistance for pennies...
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