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Advice on Filter Capacitors for this LM4780 Board

solderdude

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#21
You can leave those resistors out (as in mount a wire instead) when you want the volume level to go down to '0'
When you don't want that halve the values of R431, R531 to say 220 Ohm in that case max attenuation will be -33dB from full (0dB) to minimum.
In case you use the 10k and leave the 470 Ohm max attenuation will be -27dB
 
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SIY

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#22
When I decide to use a 10k pot together with the headphone board pictured above, do I have to alter/double the values of R431/531?
In theory, yes they should be halved, as a practical matter, probably no reason to change them.
 

Herbert

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#23
Got it! R432/532 do not have to be changed, I assume.
It will take some time to report back, many thanks for your quick answers.
Audiosciencereview has clearly become my favourite forum...
 

Herbert

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#24
I have not started yet assembling the board but the idea of using
a motorized pot came up - Looks like only 50k are available
I assume I have to change the Input resistors for this?
All the best,
Herbert
 

SIY

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#25
I have not started yet assembling the board but the idea of using
a motorized pot came up - Looks like only 50k are available
I assume I have to change the Input resistors for this?
All the best,
Herbert
Chances are, it will work fine without changes. If you want to limit its adjustment range, you can change the resistors, but you likely won't have to.
 

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