Yaqin SD-CD3 Tube Buffer - upgrading caps

Hello All,

Just had the lid off and take a fancy at replacing the caps:

4x 0.47u 275v
2x 0.22u 275v

Would like to replace them with ClarityCap ESAs, but they don't seem to make any to the same exact spec. Their 0.22u's are 630v and the 0.47u's are available in 250v and 630v.

Does this matter if they are not an exact match on the voltage ?

Many thanks

YAQINSD-CD36N8PTubeSignalUpgradeBuffer.jpg


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I recently purchased this tube buffer too. I'm split between getting better tube or putting in better caps first. It's generally a better idea to go UP in voltage values instead of down, though it maybe a challenge getting 630V film caps to fit in the case.

Currently leaning toward the cheaper end of the luxury film caps with Mundorf ZN's. Changing out the .47uF and the .22uF would be about $60USD.
 
Some brands have 400VDC caps too, they might be a better fit and should still be ok voltage wise. Best get a reading of the voltage at those caps first though. Yaquin might have been pushing their luck.

From the markings, they have used those caps: http://ch.elcomp.ch/download/Pilkor_Filmcapacitors/Folien-Kondensator-PCX2-335M.pdf They're quite commonly found as line filters in more expensive computer power supplies. As a matter of fact, they sound half decent used as coupling caps.
 
I recently purchased this tube buffer too. I'm split between getting better tube or putting in better caps first. It's generally a better idea to go UP in voltage values instead of down, though it maybe a challenge getting 630V film caps to fit in the case.

Currently leaning toward the cheaper end of the luxury film caps with Mundorf ZN's. Changing out the .47uF and the .22uF would be about $60USD.

I am tempted to go for the ClarityCap SAs as I have heard these and really liked them. More revealing caps really do my hearing in, tried the MRs and my ears are ringing like mad... Guess my hearing is on its way out, but must go what doesn't aggravate my ears
 
Bernie7: How do those Grepin CV181 sound? They look every festive! I believe all 6 blue caps are in the signal path. Looking at the board traces they are in both the plate and the grid pins. The thick blue wire looks to be the heater circuit and black Nichions are the power caps. After a few search it looks like everyone changes the blue caps and leaves the black Nichions alone.

I just ordered some NOS Sprague "Vitamin Q" 400V paper in oil caps and will be putting them in when they arrive. Hopefully they will sound decent, otherwise the ClarityCaps are cheap and I may switch over to them.
 
Swap 0.47uF for 0.22uF?

Bernie7: How do those Grepin CV181 sound? They look every festive! I believe all 6 blue caps are in the signal path. Looking at the board traces they are in both the plate and the grid pins. The thick blue wire looks to be the heater circuit and black Nichions are the power caps. After a few search it looks like everyone changes the blue caps and leaves the black Nichions alone.

I just ordered some NOS Sprague "Vitamin Q" 400V paper in oil caps and will be putting them in when they arrive. Hopefully they will sound decent, otherwise the ClarityCaps are cheap and I may switch over to them.

Grepin CV181 is festive looking :eek: and sound like it too being much better than the stock tubes, more open and airy sounding. I haven't tried other tubes.

Think I'll begin by swapping the blue caps with Dayton 0.47uf 400V caps that I have. These are cheap and pretty good sounding. Any idea if swapping 0.47uF for the 0.22uF pair is a no-no? If these are in the signal path I would think there's no harm.
 
Think I'll begin by swapping the blue caps with Dayton 0.47uf 400V caps that I have. These are cheap and pretty good sounding. Any idea if swapping 0.47uF for the 0.22uF pair is a no-no? If these are in the signal path I would think there's no harm.

Hi,
Because capacity is doubled you have a lower low frequency extension
so you will hear more bass which is better.:) singa

PS there is no necessity to change the 4 power decoupling caps as it will
not have a significant improvement or none at all.A upgrade to mundorf
silver/gold or silver/gold in oil or at least silver in oil will be worth your while.;)
 
Hi,
Because capacity is doubled you have a lower low frequency extension
so you will hear more bass which is better.:) singa

PS there is no necessity to change the 4 power decoupling caps as it will
not have a significant improvement or none at all.A upgrade to mundorf
silver/gold or silver/gold in oil or at least silver in oil will be worth your while.;)

Thanks for the input singa :)

I did change the four .47uf caps earlier to Dayton and imo there was a noticeable improvement to the sound, seems clearer and more detailed. Will try the ultimate, ie mundorf one day, right now having fun rolling caps ;)
 
Ok got round to replacing all six caps under the hood (4x0.47uf and 2x0.22uf). Opted for ClarityCap SA's because they are a known quantity, not expensive and they fit ! Substantial improvements all round. Only run in some 8 hours and notice far more detail in the mid, plucking guitar strings and voice's re-verb are now there and tactile, bass has more extension, nothing new in the highs, but they are still not burnt in yet.

All in all very worthwhile, no going back.

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Re-Capped with NOS Sprague Vitamin Q's. My experiences echo BarbieBoy's! This should be a must do mod! Going to wait until they burn in completely before do a final report on sound. I thought they would be very warm and romantic being a old PIO cap but they are surprisingly clean and clear sounding with great extension.

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Just wanted to update this thread and say that I've been enjoying this little Yaqin buffer immensely hooked up between my Squeezebox touch and vintage Marantz.

However sometimes I think the gain is a little on the high side. Anyone have any idea how to adjust the gain on this unit? I see several resisters on the board and wonder what would happen if I changed the values.

Also I'm playing with the idea of increasing the input capacitors, the 2 .22uf ones near the front of the unit. I've read that may increase bass response.

Any suggestions?