I plan to drive this amp directly from CD player because of it’s sufficient input sensitivity, but that requires connecting a volume pot (let’s say 50k/log) somewhere to the signal trace. There are three possibilities commonly used:
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between the input stage and the power amp - hot pin to opamp output, middle pin to power amp input, cold pin to ground. This is certainly the best solution for noise reduction, but I’m afraid volume pot will interfere with power amp feedback (R18, C13, R3) depending on it’s position.
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between the input coupling cap and the input opamp - right noninverting channel should work well, but I’m afraid again about the inverting channel feedback, changing position of the volume pot (hot pin coupling cap, middle pin R2, cold pin ground) will interfere with opamp feedback (R12, R13, R15, R2) and change it’s gain.
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in front of the coupling cap, so that pot works 100% like a passive attenuator. Will the coupling cap in this case sufficiently divide volume pot and the input stage? Will not the amp suffer from it’s non-symmetrical input design?
Have anyody out there tried to connect a volume pot directly to this amp? Lotta thanx for any ideas!