Doug Self Preamp from Linear Audio #5

It's not a complaint. I was just wondering if degradation of the oxide layer is a "thing" like with polarised electrolytics, admittedly probably only those used in PSU's. I couldn't find any information about it anywhere, so I'm presuming not, but thought I might ask here.

It's always good to ask. I have noticed that I seem to blow up fewer parts these days than what I did 20 years ago. There is very little evidence that I am any smarter. I suspect the parts in question are better built and can survive more of my abuse.
 
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Hi Carl,
I use polarized electrolytic cap as recommended by Doug Self. i have 35V Elna Silmic II. C14 on your Schematic and PCB is reversed for same C14 in Linear Audio Vol 5 article page 150. Could you confirm that the schematic in Linear Audio Vol 5 article is the one that is correct? if yes i have to reverse C14 on your PCB. Thank
 

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Hi Carl,
I use polarized electrolytic cap as recommended by Doug Self. i have 35V Elna Silmic II. C14 on your Schematic and PCB is reversed for same C14 in Linear Audio Vol 5 article page 150. Could you confirm that the schematic in Linear Audio Vol 5 article is the one that is correct? if yes i have to reverse C14 on your PCB. Thank

That's a really good question that has not been asked before! Orientation didn't matter with the caps that I used, but ...

if you are building with polarized Silmics, I would follow the direction as published in the Linear Audio article.
 
Did anyone measure the offset voltages? Since the offsets are so low, I do not think polarity is problem.
When in doubt I use Nichicon UES or film.
DougS has written that he prefers large V and C to minimize the low freq THD in ecaps.
I also read that someone in the forum measured ecap thd on a number of models/brands, the Nichicon Muse BP UES series was the winner, but only marginally.
 
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Did anyone measure the offset voltages? Since the offsets are so low, I do not think polarity is problem.
When in doubt I use Nichicon UES or film.
DougS has written that he prefers large V and C to minimize the low freq THD in ecaps.
I also read that someone in the forum measured ecap thd on a number of models/brands, the Nichicon Muse BP UES series was the winner, but only marginally.


THD is not a function of brand or V.
 
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I also first attempted using Hicoco's version of the back panel, and found that it didn't fit (a few millimeters off on many parts).

I'll measure myself and will order a new back panel from Schaeffer when my measurements are done. If the new panel fits the board, I'll post the Schaeffer / Frontpanel Express file in this thread.
I'm sorry, but I should have advise that I had not used Rick G's post # 876 files yet..
you are right, unfortunately that it don't fit...i am changing right now the measurements...
Carl by any chance, do you have the quad rca phono socket pdf datasheet?
Thanks
 
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