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capacitor upgrade on my tube phono stage

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Hi everyone, and thanks for looking at my thread.
Ive been using my Icon Audio phono stage for a while now and recently upgraded the tubes to Mullards. the company offers an upgrade with paper oil caps but at £200 its a bit expensive for me.
Can anyone offer any advice on doing it myself?
Im good with a soldering iron but have no knowledge of electronics. Is it just a case of matching the values of the new caps to the existing ones or is their a bit more to it. Thanks, look forward to any responses
 
Hi everyone, and thanks for looking at my thread.
Ive been using my Icon Audio phono stage for a while now and recently upgraded the tubes to Mullards. the company offers an upgrade with paper oil caps but at £200 its a bit expensive for me.
Can anyone offer any advice on doing it myself?
Im good with a soldering iron but have no knowledge of electronics. Is it just a case of matching the values of the new caps to the existing ones or is their a bit more to it. Thanks, look forward to any responses

£200 is very steep! When 'upgrading' you need the right capacitance value, the right working voltage value, an appropriate tolerance (%), and an appropriate temperature rating. If it is to pass significant current then the ripple current rating is also important, however this is unlikely in a phono stage.
 
If you can solder, there is no reason to not try it yourself! You might try Russian military surplus paper in oil caps (K40Y-9's) or teflon caps (FT-3). They are very well regarded, and won't cost you nearly as much as audiophile eye candy. You can find them most easily on Ebay (watch out, there are many, many types of Russian surplus caps, and not all are desirable). Check first to see how much space you have. Often fancier caps are big.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers
 
Hi everyone, and thanks for looking at my thread.
Ive been using my Icon Audio phono stage for a while now and recently upgraded the tubes to Mullards. the company offers an upgrade with paper oil caps but at £200 its a bit expensive for me.
Can anyone offer any advice on doing it myself?
Im good with a soldering iron but have no knowledge of electronics. Is it just a case of matching the values of the new caps to the existing ones or is their a bit more to it. Thanks, look forward to any responses

Search on ebay PETP capacitors, they costs 2 cents and are simply great!!
 

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I just ordered some K73 to try out.
I also ordered some .5uF silver micas, more k40-Y .22 200 and 400 volts, and more FT3. I've got around 30 of the .22 uF 600V K40Ys on hand.

I like to play around rebuilding Scott and HeathKit point to point wiring tube gear and always replace the coupling caps with Russian PIOs I'd love to fit in Russian teflons, but can find the space. I did however fit 2.2 uF in my monitor cross overs, stunning change after many, many, many hours of break in.

As long as you won't damage anything removing the old caps, I'd try Russian mil surplus ones. Keep in mind, they all take a long time to break in.

Best from Tucson AZ
Bob
 
Since you aren't checking to see if a cap is bad, a multi test that does caps will give you the cap value and you'll use the testers to measure the voltage of the circuit.

The rule of thumb I was given is to double the circuit voltage when buying caps.

If you are buying a multi meter, consider getting one that measures inductance also. With that, you can have FUN upgrading components in speaker cross overs.

Best from Tucson
Bob
 
I would not use silver micas anywhere in the signal path.

Actually while I generally agree there are some strange Russian silver micas that seem to perform quite well, good linearity and good sound as well. Not typical of my experiences with mica in general. I have heard a couple of diy phono stages that used them and heard an A/B between polystyrene and Russian silver mica, it was a hard call, but I think I might have slightly preferred these SM types.
 
I recently bought a Dynaco FM-3 to rebuild. I ordered new resistors from Mouser and looked at buying some silver micas for some of the small value caps. For not much more than silver micas in low pf values, I was able to get the Russian milsurplus .1mf. At those prices, gotta try 'em. Wish I could figure out how to get those big mil surplus ones on the printed circuit board in place of those dinky little ones. I need some help from Dr Who to get those big caps in small spaces. Thats what we need TARDS caps.
 
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