Before I got on here and found out how much experts here hate ceramic caps in the music path, I stumbled on some Aerovox COG 50 V 10 uf caps on sale at newark. I had a lot of 10v 10 uf electrolytic coupler and filter caps to replace in the preamps of a 1967 organ, and in many cases the 63 v roedenger film alternative would not fit. I wasn't putting electrolytic back in, life is too short to replace parts every decade or so. So I used the Aerovox gold ceramics. I love the difference in sound from the dried up e-caps, many more frequencies make it through the cap. I also had a power amp I rebuilt from a toasted wreck in 1987? with new tantalum 5 uf input caps. The amp had a popcorn noise at all times after I got it online, I found very annoying. I replace these tantalum caps in 2010 with 50 v X7R Aerovox 4.7 uf ceramic caps with a huge improvement in sound. So despite the known non-linearities of ceramic caps, I think you can swamp that effect by using 50v caps on <1.5 v application. Of course, for cartridge loading you are down in the 25 mv signal range. IMHO the same linearization effect applies, the longer the curve, 25v or 50v, the straighter the part of the curve your application is using. Of course, if you can get COG ceramic that is great, but putting fans on my power amp to prevent it from melting solder on the output caps or thermally running away, really reduced the importance of the temperature effects on the input caps. The same is true of my organ, the preamp areas are well away from the motor and tube power amps that generate the heat.
Have fun experimenting. WIMA is a brand I find only on salvage parts; here in the states to buy them you have to pay shipping from a single line supplier at about $8 a box. I can get Sprague Orange Drops or Vishay Roedinger from my nearest big supplier, however, so those are what I experiment with in replacing electrolytic caps. 150 electrolytic caps replaced since retirement, 115 more in that organ, maybe 400 to go in another organ, a power amp, a mixer, a graphic equalizer, an effects chassis, a computer, a 1985 sampler keyboard, a television etc etc etc.
Have fun experimenting. WIMA is a brand I find only on salvage parts; here in the states to buy them you have to pay shipping from a single line supplier at about $8 a box. I can get Sprague Orange Drops or Vishay Roedinger from my nearest big supplier, however, so those are what I experiment with in replacing electrolytic caps. 150 electrolytic caps replaced since retirement, 115 more in that organ, maybe 400 to go in another organ, a power amp, a mixer, a graphic equalizer, an effects chassis, a computer, a 1985 sampler keyboard, a television etc etc etc.
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And his concluding remark "
We choose adequate decoupling values to suit the duty.
eg.
we have a typical 100nF X7R operating at 40Vdc as decoupling and we have found that the circuit is very resisiliant to Rail variations. It matters not that the actual 40Vdc capacitance is 80nF, or 50nF, or even 20nF. What matters to DIYers that the the supply rail does not ripple excessively.
We do not care that the 100nF is ten times bigger than a 22nF 402 X7R that has a guaranteed 40Vdc capacitance of 17nF. We are not striving for absolute cheapest cost by adopting smallest size and smallest board space.
does not apply to us DIYers.
We choose adequate decoupling values to suit the duty.
eg.
we have a typical 100nF X7R operating at 40Vdc as decoupling and we have found that the circuit is very resisiliant to Rail variations. It matters not that the actual 40Vdc capacitance is 80nF, or 50nF, or even 20nF. What matters to DIYers that the the supply rail does not ripple excessively.
We do not care that the 100nF is ten times bigger than a 22nF 402 X7R that has a guaranteed 40Vdc capacitance of 17nF. We are not striving for absolute cheapest cost by adopting smallest size and smallest board space.
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