NAP250 MOD amplifier 80W by LJM

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Hello!! Help please. I need to reduce the gain. somebody has a schematic of this product
 

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It is reasonable to expect a lot of similarity with the original NAP250 circuit.

On a casual glance, the resistors controlling gain should be the ones circled. Be careful adjusting the values as there is a pretty good chance the circuit may become unstable without correspondingly adjusting the compensation.
 

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Yes, that's the wrong question to ask about about a power amplifier. The amplifier and all basic power amplifiers require a preamplifier which has a volume control, or you can just add a volume control pot after the input socket if the amplifier has adequate gain. See this similar thread for some details: How to control volume on DIY Amplifier?

I'd try a 20K or 50K logarithmic taper type. If you want it to work smoothly and correctly, buy an ALPS RK27 copy. Even the Chinese copies are expensive but that's what you see fitted to most DIY kit preamp/amps.
 
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