The tinned copper Duelunds are exceptional ,a bit more top end then just copper foil, and their oiled paper in a deep vacuum and same resin as the cast .
i have in my coda CSIB integrated amp a 1UF coupling cap , I tried a .022 vhaudio Cutf great detail but 2d , used same .022 Duelund jdm silver foil oil very nice and open and smooth , just as a hunch I bought the Duelund1 uf coupling cap
no bypass caps the JDM tinned copper foil paper oil , it is Huge almost 3 x as big as theJupiter copper foil 1 uf , IHave pictures ,ihad to relocate it to the edge of the board below ,butWow itwas well worth it , I compared withtheWaay overpriced cast Duelunds
guess what almost exact , same size ,weight over-a pound I would guess ,
just a bit longer vacuum and their silver thicker leads with cotton ,and the cast almost 150% more,$$ the jdm only go up to 2.2 uf if youcan fit them ,the best capacitor out there period for electronics and loudspeakers ,if using for a bypass cap 3% or less a great rule of thumb ,a nice natural detailed warm performance,give them at least 300 hours to fully runin, after 💯 + hours they start to open up nicely !!