128 step attenuator on alephP1.7 - diyAudio
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Old 17th November 2011, 09:59 AM   #1
vivanco is offline vivanco  Italy
diyAudio Member
Join Date: Jan 2011
Default 128 step attenuator on alephP1.7

hi my friends,
I have a problem with my DIY Aleph P1.7 project, that I realizzado using a pcb version mother board on which there is also the volume control similar to that proposed in the original project of big Nelson Pass, with the difference that it is designed on the 128 steps;
the relays, which manage the steps, are seven per channel;
the resistance values that contribute to the attenuation control are different from those indicated it's original design Pass, and specifically as follows:
267 - 620 - 1.43 K - 3.32 K - 7.87 K - 18K - 43.2 K
exactly my problem is the management of the attenuation of the volume, when I start to turn the potentiometer which acts on the controller until you have the first of the first relay switch which is the first step, the audio level is not suited to a night listening ,,, I did all the inspections, which excluded abnormalities mounting components and malfunctioning of the control circuit, I have the feeling that the problem lies in a not correct scale of values of the resistors, what do your think about ?
Thanks in advance to all those who will respond to this 3D

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