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

I don’t see the need to excuse rude and obnoxious behavior.

I was just joking around a bit to ease the tension.

But to be honest I do not take any comments personally. Unfortunately there is always some character lurking around a forum who is unhappy and wants to share that negativity with others. I see it more as a cry for help than a personal attack.

Mind you this forum thankfully is pretty good and positive. When I was on some guitar forums there were a lot of mean spirited people attacking each other. I do not bother with those places anymore.

 

Take pictures of every section you are working on before you start and after you finish

Very good advice. Especially when there is no schematic available!

But to be honest I do not take any comments personally. Unfortunately there is always some character lurking around a forum who is unhappy and wants to share that negativity with others. I see it more as a cry for help than a personal attack.

Good points and I see more clearly your perspective. You have received some very good insight on this thread. I look forward to your listening outcomes.

Charles

@millercarbon 

What I have found useful:

https://www.humblehomemadehifi.com/Cap.html

I just wanted to take a minute to thank you for the link. It was indeed very helpful.

I can definitely hear a difference in the clarity of vocals and the separation of instruments between the X7 vs the X9 and X10. So let’s see how this upgrade works out once I get the parts.

There’s a lot more going on than just the caps. Power, impedance, source, cables, loudspeaker, tube age, wire, sockets, etc. etc. Change one thing, change everything.

To those who don’t like the tone:

Are you fine with people being seen off by charlatans that give bogus reasons with ZERO supporting evidence other than their say so? They think their system sounds the same every day or that they can turn it off for some time, make a change and then determine a delta. Ha! Qualified engineers listen for weeks, making comparisons between a reference unit and the changed. Confirmation bias plays a huge part in an awful lot of opinions.

I’ve been at the HiFi game for more than 50 years, Grammy nominated engineer and if you saw a movie from about 1990 to 2010, quite possibly the soundtrack was recorded through something I designed.

Some posters blather on about changes without the slightest regard for rigor. To boot, they evaluate whilst intoxicated and at injurious levels. I endured too many sessions with doped up musicians to have any tolerance for audiophools.

PAX.