As several DIYers out there, I’m a big fan of the Russian teflon FT-3 capacitors in my preamps. I normally use the 220nF/600V ones as have plenty of them in stock. These are superb in my view, however mounting them is a royal pain in the back. I used turrets for some time, but I ended up building a simple PCB which has a cutout to fit the FT3, solder it firmly on big copper pads and then solder the connections from the PCB. Also added a bias resistor (either for charging/discharging the cap or for fixed bias) which is connected to a GND terminal. This GND terminal could be used for the negative fixed bias if required. The PCB can be stacked very easily as has 4 M3 hex standoffs:
Do you have PCBs for sale?
Dear Alex, if you like ft3 you really go in the bad way. Clearly Jupiter, Duelund, Audyn cooper or Myflex are ten times better. All time that you invest in your system can not devaluated to safe a few $$$.
Sorry, you missed the point here. This isn’t about which capacitor you prefer the most. Frankly, I tried them nearly all and am using Myflex for example on my current 300B Amp. If I can, I avoid the coupling caps where possible. That may end up with a bigger and more expensive system generally. You can see that my designs are mostly not bothering about cost. But personally I think that the boutique caps are overrated. I find the FT3 to be a great compromise in cost vs quality.
I would agree with Ale on this, the FT3 shouldn’t be judged until you have at least 100 hours on them, Miflex are a lot cheaper than other Copper foil Capacitors & indeed very good, but make no mistake they will not make up for a badly implemented design imho!