Duroch Capacitors

Duroch are metalized film capacitors - metalized aluminum film. They are ok but far from great. 

PL used to use SCR caps (also metalized film) from France but switched to Duroch. The Jupiter copper foil caps are a ton better. Much more organic sounding. Much better imaging; less smear. 

If you want to change the caps the first one to change are the 0.1uf film caps filtering the voltage to the input tubes. 

If you are interesting in modding or switching caps a good trial to do is to get low uF Audyn TrueCopper (0.1 or so) and bypass the output caps.  Make sure to get the right V rating equal to or exceeding the existing (especially important in tubes).   See if you hear a major difference.  If so, you may want to go all copper foil but they are often very physically large. 

"made to our specifications" could easily mean "they wrote our name on their usual caps for us." 

they could be anything, not likely custom made. im curious. id like someome to find out exactly what they really are. 

Besides the Nichicon 22mf 450v electrolytics, which of the DuRoch capacitors pictured would you immediately change for better sound quality?

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