I use .22 600V coupling caps (4) and (2).33 600V input caps and I use them because I haven't heard better caps. They are so clean, detailed, and get out of the way amd impart little to no imprint on the sonics. Many caps are heard, these just let everything through. Many polypropylene are fine, but the extremes are just a little rolled. Read the numerous reviews out there on capacitor shootouts and I have to say, the reports were accurate. I have tried many caps and these just are very special. I may try his new ones that are copper teflon, not tin/teflon. I will sell the .22 and .33 when that happens at a good price. Probably at the 25 piece price, about 40% off. The only ones that may be competitive are the Audience Teflon and the Silver Audionote. I have heard the Audionote in another amp and was not bowled over by the sound. But....not in my circuit so I am witholding judgment. At the Audio Note price, that is just ridiculous. Jallen