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Question About Capacitor Upgrade in Tube Amp

Hi,

I am preparing to do a coupling capacitor upgrade on a recently purchased tube integrated amp. The two 0.22uF on the preamp tubes are fairly straight forward. But I noticed another similar model 0.33uF cap on the large filter capacitor for the B+ supply that is installed across the hot lead to ground.

Does this cap on the B+ just block high frequency noise from the power supply or does it have any effect on the amp tone? Is there any reason to "upgrade" this cap?

I know it may be hard to tell exactly what is going on without a schematic.

Also any recommendations on a good cap to use in the upgrade of the coupling caps? I was looking at Mundorf SilverGoldOil for the quality at not too crazy a price. The amp already sounds good but lacks a little clarity that I think a coupling cap swap will help with. It is SET 300B amp.

Thank you!

 

calieng
dekay's avatar
dekay
5,349 posts
 

I have inexpensive Jantzen (2.2) red colored caps in my Bottlehead Paramours that sound excellent.

Been thinking about going SS, but if I don't I may try the Jantzen silver colored caps which are said to have a bit more detail.

I don't recall what was in their originally (been using them for 20 years now).

I looked @ Audyn  copper when they first came out, but 2 of them cost twice as much as I paid for the amps/mono-blocks.

However, if you go with Zipost's advice don't stop there as you can also downgrade your speakers, cables, source gear and maybe even the tubes if you are lucky.

 

DeKay

jmolsberg's avatar
jmolsberg
467 posts
 

I like these 

 

 

charles1dad's avatar
charles1dad
10,230 posts
 

Bottlehead is a good example for illustration. They are inexpensive and thus a low barrier of entry for budget buyers. Although low cost, they are consistently well designed and engineered. They are good candidates for upgrading to better quality parts due to their solid engineered foundation. They will definitely respond to higher quality capacitors/resistors/transformers/tubes etc.

Charles 

calieng OP
144 posts
 

Thanks for the replies so far.

Did anyone know if the .33uF on the B+ filter cap is just for noise filtering on the power supply or does it have any effect on the amp sound? I probably will just leave that one alone unless someone one here has some advice for that one.

I will check out those other caps mentioned.

Thanks!

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