Upgrade Capacitors

[Paul Birkeland]

It's also important to consider the AC component, especially with those parallel feed capacitors.  In the Stereomour, for example, we have 300V DC plate to cathode across the cap, but when you put signal through that 2A3, there's  potentially 120V of AC plate signal riding on top of that.  A 400V-500V rated cap is not going to like this, but the 630V cap has the margin tolerate this abuse. 

[Adrian]

Voltage ratings are a bit of an over-simplification. Here's a 4-page white paper from CDE:

http://www.cde.com/resources/catalogs/filmAPPguide.pdf

On page 3 at the bottom right there is a plot of lifetime vs. temperature and voltage, which gives a more nuanced picture.

It's also important to consider the AC component, especially with those parallel feed capacitors.  In the Stereomour, for example, we have 300V DC plate to cathode across the cap, but when you put signal through that 2A3, there's  potentially 120V of AC plate signal riding on top of that.  A 400V-500V rated cap is not going to like this, but the 630V cap has the margin tolerate this abuse. 

Paul & P.B.
Excellent resource and information guys.
Always learning and moving forward.
Thanks

[Analogluvr]

Paul, or anyone, do you hav another source for the Russian caps you mentioned?  I was scouring eBay and cannot find those particular ones, and I like the looks of them as they have a 1% tolerance.  If I find a pair I'm going to shoot them out against the mundorf sio that I have in there now.

[physicsmajor]

@Analogluvr It seems the K73 line of Russian caps came in a few different flavors/packages.

There is seller from Ukraine advertising packs of 8 of the K73-16 variant for $30. These are PETP but axial mount, reasonably sized, and probably actually easier to use in the build.

However, before you go running off to buy them from that guy, the reason I know this is because I just got a pack of 8 in for my BeePre - but I don't need the other 4 

Shoot me a PM if you'd like to experiment with these at cost.

[kip.duff]

@Analogluvr It seems the K73 line of Russian caps came in a few different flavors/packages.

There is seller from Ukraine advertising packs of 8 of the K73-16 variant for $30. These are PETP but axial mount, reasonably sized, and probably actually easier to use in the build.

However, before you go running off to buy them from that guy, the reason I know this is because I just got a pack of 8 in for my BeePre - but I don't need the other 4 

Shoot me a PM if you'd like to experiment with these at cost.

I'm starting to build my BeePre- I'll buy them if still available and the other member doesn't want them.   

[rockpassion]

Hello All,

I replaced the 10uf coupling capacitors with the Russian Teflon FT3 Capacitors.  While they are not nearly broken in I have noticed a major improvement in the bass, it is now much deeper and more powerful.  The next thing is clarity in the soundstage.  I can really hear instruments more distinctly and clearer placement.  Plus, there is just an overall smoothness I did not have before.  The highs have mellowed a little (which is good in my system) but they are still real nice.

All in all, given input by others these might take up to 400 hours to break in.  Should be a fun journey. 

Richard

[cktc]

I don't see Russian Teflon FT3 has 10uf big values? are you using small value like 0.1uf to bypass the original 10uf?

[Chris65]

I don't see Russian Teflon FT3 has 10uf big values?

They don't, well not that I've seen. Generally available are 0.1, 0.22 & 0.47uF values.

[rockpassion]

Gentlemen,

You are right, the capacitors are K75-10V, PIO.  Sorry about that.  The FT3's were put in my Eros. 

Even these I believe are much better than the stock Capacitors.  The big issue is the size.  They are about 3 inches long and about 1.5 inches in diameter.  The fit but just barely. 

Richard

[aroide]

I had upgraded my caps with Claritycap MR 10uf and have been happy with the sound for a few years.  But Icant leave well enough alone.

I had 4 Mundorf Supreme silver/gold/oil 2.7uF caps I intended for my Rogue Atlas Magnum amp, but they won't fit.  So I put 2 in my quickie preamp (effectively tripling the cost of the quickie) in the bedroom and WOW what a change.

I just replaced the Claritycaps in my Bee Pre with the Mundorfs and after 75 hours or so of breaking so far, they are taking my sound to another level of imaging and 'booginess'.  I'm sitting here listening to Elton John on vinyl and can't stop moving.  At 20 hours they sounded horrible like a really cheap cartridge.  I'm guessing I need 150 hrs or so to be considered fully settled in.

Question on the value of 2.7uF vs original 10uF... I've read in other threads that this value should be fine for coupling.  But should I be concerned about anything? Rogue has 1Mohm input impedance.

[oltmb]

There is an online calculator on the V-Cap website that helps you to determine the right capacitance for your system. Very useful.

[oltmb]

I purchased the Mundorf Supreme Silver Gold 3.3 uF and when they arrived they looked too big to mount them. So I decided to put them on eBay, but there were no buyers and they were lying on my desk and I decided to give it a try. I mounted one on the orginal position and the other one was mounted vertical as the BeeQuiet was taking up space. The leads of the Mundorf capacitors are thick and by soldering they would stay in position but I used tie-wraps to fix them.

The sound impression after power-on was noticably better, more open and detailed but I need to have them run in for some time.

(https://image.ibb.co/kpHTWQ/Mundorf.gif)

[Doc B.]

If we made a preamp as big as a Volkswagen someone would make a capacitor as big as a Cadillac, and someone else would be determined to put it in the preamp. 

[caffeinator]

Something about that (Cadillacs and Volkswagens) reminded me of those old hot rod monster cartoons (see linked image) which inspired my little illustration (a little off the topic of this thread, as it's more headphone-centric than BeePree centric, but so be it).

https://www.google.com/search?q=monster+cartoons+hot+rod+60%27s&tbm=isch&imgil=rnwmkiyzmZU8yM%253A%253BeVIaUyVJnNzblM%253Bhttps%25253A%25252F%25252Fwww.pinterest.com%25252Fkevinwollershei%25252Fchildhood-bubble-gum-cards%25252F&source=iu&pf=m&fir=rnwmkiyzmZU8yM%253A%252CeVIaUyVJnNzblM%252C_&usg=__GxuHrlAqWN0gGt6lk7L8ClgiSR0%3D&biw=1320&bih=760&ved=0ahUKEwi0mc_LtbPTAhXGy1QKHZHtD6QQyjcIMw&ei=89z4WPTTI8aX0wKR27-gCg#imgrc=rnwmkiyzmZU8yM:

[2wo]

That's great, you should have your own badge made...John