mudihan
100+ Head-Fier
- Joined
- Mar 13, 2005
- Posts
- 271
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- 11
Happy holidays!
So the old potentiometer has become very scratchy. My solution was to bypass it and use an outside digital potentiometer instead (I also changed R102 and R202 from 910k to 50k). The problem, however, is that my DAC outputs a healthy 2.1v and so the amp is already very loud when the digital potentiometer is only at 40%. And that's just for classical music. For those loudness "winners" popular tracks, 25% is enough. If the amp's gain is set by resistors, please point me to them so that I could play with the values to lower the gain.
Also the 2w 27k resistors appear to be carbon composite resistors. I am thinking changing each pair to a single film-type resistors of either 51k or 56k rated for >5w for lower noise and better stability. I have found 5w metal dioxides rated for 800v, but just saw Caddock MP925s that are rated for 500v and 25w (if mounted on a heatsink). Any sonic benefit of using the Caddocks vs metal oxides (or even wirewounds)?
Many thanks!
So the old potentiometer has become very scratchy. My solution was to bypass it and use an outside digital potentiometer instead (I also changed R102 and R202 from 910k to 50k). The problem, however, is that my DAC outputs a healthy 2.1v and so the amp is already very loud when the digital potentiometer is only at 40%. And that's just for classical music. For those loudness "winners" popular tracks, 25% is enough. If the amp's gain is set by resistors, please point me to them so that I could play with the values to lower the gain.
Also the 2w 27k resistors appear to be carbon composite resistors. I am thinking changing each pair to a single film-type resistors of either 51k or 56k rated for >5w for lower noise and better stability. I have found 5w metal dioxides rated for 800v, but just saw Caddock MP925s that are rated for 500v and 25w (if mounted on a heatsink). Any sonic benefit of using the Caddocks vs metal oxides (or even wirewounds)?
Many thanks!