Beetle, I am glad to be here. My hi-fi life has been fairly well buried until recently. Nice to find you guys.
Regarding capacitor bypasses, we discovered in the 1970s what has now become fairly commonplace knowledge, that small value high-grade capacitor(s) in parallel with the workhorse will keep the upper frequency leading-edge waveforms, etc. intact at a higher performance level per cost than a single type cap. My brand knowledge is a couple decades old and lots of progress has been made, so I will be finding my solutions just like you guys. We don't have Jim's lab and expertise. Nonetheless, Thiel's development MO was to experiment with cap configurations via blind listening to rank sound quality among the combinations. Then the highest performance / cost solution was identified and subjected to rigorous analysis regarding waveform integrity, ringing and so forth. The winner was always a bypass pair or triplet. The rank of (affordable) cap types (at that time) from best downward was: Teflon, Styrene, Propylene (foil or metalized depending on current requirements), Polyester (Mylar) and electrolytic, with some variants such as Tantalum, oiled, etc. Mylar was a bargain because propylene was very expensive due to production losses, which is now cured. Notice that older Thiels contained multiples-in-series propylenes or mylars to make the value in order to reduce costs. (Eventually a wound film cap will fail in testing due to a thin spot in the film carrier, so cost rises geometrically with cap value.) Another thing that has changed is that Styrene caps (our favorite bypass) has been obsoleted in the marketplace. Teflon over propylene and/ or electrolytic has a high likelihood of success on those large value caps. Rule of thumb is to bypass at 1% to 10% total requirement, more or less. More for high current requirement. Example: 100uF EE + 10uF PP + 1uF Tef > 111uF value at much lower cost than eliminating EE.
This whole upgrade enterprise runs contrary to the rigor we applied at Thiel Audio. But I am fairly comfortable flying blind since I do not have access or time to test with instruments. I am also fairly confident of my approach due to serious personal experience. I also will employ a few twenty-somethings including two young women with extraordinary hearing to supply observations beyond my present hearing acuity (I am 69 and ears suffer with age.)
That's all for now. I'm expecting 4 XO kits for my PPs this week from Rob. I'll open my cap investigation and layout next week.
Regarding capacitor bypasses, we discovered in the 1970s what has now become fairly commonplace knowledge, that small value high-grade capacitor(s) in parallel with the workhorse will keep the upper frequency leading-edge waveforms, etc. intact at a higher performance level per cost than a single type cap. My brand knowledge is a couple decades old and lots of progress has been made, so I will be finding my solutions just like you guys. We don't have Jim's lab and expertise. Nonetheless, Thiel's development MO was to experiment with cap configurations via blind listening to rank sound quality among the combinations. Then the highest performance / cost solution was identified and subjected to rigorous analysis regarding waveform integrity, ringing and so forth. The winner was always a bypass pair or triplet. The rank of (affordable) cap types (at that time) from best downward was: Teflon, Styrene, Propylene (foil or metalized depending on current requirements), Polyester (Mylar) and electrolytic, with some variants such as Tantalum, oiled, etc. Mylar was a bargain because propylene was very expensive due to production losses, which is now cured. Notice that older Thiels contained multiples-in-series propylenes or mylars to make the value in order to reduce costs. (Eventually a wound film cap will fail in testing due to a thin spot in the film carrier, so cost rises geometrically with cap value.) Another thing that has changed is that Styrene caps (our favorite bypass) has been obsoleted in the marketplace. Teflon over propylene and/ or electrolytic has a high likelihood of success on those large value caps. Rule of thumb is to bypass at 1% to 10% total requirement, more or less. More for high current requirement. Example: 100uF EE + 10uF PP + 1uF Tef > 111uF value at much lower cost than eliminating EE.
This whole upgrade enterprise runs contrary to the rigor we applied at Thiel Audio. But I am fairly comfortable flying blind since I do not have access or time to test with instruments. I am also fairly confident of my approach due to serious personal experience. I also will employ a few twenty-somethings including two young women with extraordinary hearing to supply observations beyond my present hearing acuity (I am 69 and ears suffer with age.)
That's all for now. I'm expecting 4 XO kits for my PPs this week from Rob. I'll open my cap investigation and layout next week.