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Old 5th January 2017, 03:15 AM   #1931
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my friend I do not sell anything . After tested it well, I can also share gerber file and so you can carry in your own.
thanks, waiting for the gerber file then
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Old 11th January 2017, 01:36 PM   #1932
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I've not been following along very closely here, are we talking about decoupling for the AD844? If so then I'd use several 10uF/1206 X7R between the pins as 100nF isn't nearly enough to be using for decoupling a classAB output stage (such as found in AD844).
abraxalito,
Today I tried 10uf/1210 X7R on the buffer op amp and the result is great. Many years ago I used 10uf electrolytic but it did not satisfy me. 100nf film or C0G is still better than electrolytic here. However, 10uf X7R is different story. The bass is clean and powerful. After few hours of run-in, mid and high improved, they are now equal to the effect of 100nf C0G. Thanks for the tip.
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Old 13th January 2017, 04:45 PM   #1933
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@canvas ... Hi canvas. Interesting read this:

Quote:
Today I tried 10uf/1210 X7R on the buffer op amp and the result is great. Many years ago I used 10uf electrolytic but it did not satisfy me. 100nf film or C0G is still better than electrolytic here. However, 10uf X7R is different story. The bass is clean and powerful. After few hours of run-in, mid and high improved, they are now equal to the effect of 100nf C0G. Thanks for the tip.
Have you tried to parallel a 100 nF C0G with the 10 uF X7R? I personally have good experiences with C0Gs (in another context though) and I reckon that the combination could be very fine ... As it is I'm also looking for some superb (the very "best" what that may be) 10 uF capacitors, and the electrolytics I've listened to have - to my ears - not had the fullness or other qualities of their larger value siblings (I have tried some including NP types). Might I ask which X7Rs you have tried (& listened to)?

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Jesper
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Old 14th January 2017, 03:27 AM   #1934
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Hi Jesper,

Yes, I finally paralleled another 100nf C0G to further improve the HF. I'm still evaluating this combo. Having listen to various albums, so far so good! BTW, my 10uf X7R is from TDK, 1210 rated 100V.

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Old 14th January 2017, 04:25 AM   #1935
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Today I tried 10uf/1210 X7R on the buffer op amp and the result is great.
Thanks for sharing your feedback. But don't stop at just a single cap, try adding two three or four I have some circuits where I've piled up caps atop a chip to about 10mm height.

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Many years ago I used 10uf electrolytic but it did not satisfy me.
The weakness of a 10uF electrolytic is going to be its high ESR. Typically will be an ohm or so. 10uF ceramics have ESRs considerably lower.
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Old 14th January 2017, 01:32 PM   #1936
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But don't stop at just a single cap, try adding two three or four I have some circuits where I've piled up caps atop a chip to about 10mm height.
I am thinking about stacking five 2.2uf X7R instead of one 10uf. I am not sure if this will further lower the ESR, since MLCCs are multi-layered. One thing about 100nf C0G. I found it sounds more balanced when soldered on both rails (one end at + and the other at -). According to some datasheets, this will improve distortion and PSRR.

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Old 15th January 2017, 09:42 AM   #1937
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I have also tried x7r caps as for bypassing some dac ic and opamp and got very good result.
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Old 15th January 2017, 09:53 AM   #1938
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abraxalito,
Today I tried 10uf/1210 X7R on the buffer op amp and the result is great. Many years ago I used 10uf electrolytic but it did not satisfy me. 100nf film or C0G is still better than electrolytic here. However, 10uf X7R is different story...
Have been doing this for many years, but please also use these on DAC's power supply pins - especially delta-sigma DACs benefits as they switch to rail and noise there becomes instant jitter quicker than instant coffee. In fact, use them everywhere, not just on opamps - that is why I bought 500 last time.

.
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Old 15th January 2017, 10:59 AM   #1939
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Very true, I used two 4.7uf x7r caps and one 10nf c0g in parallel for the supply pins of the AK4396 chip and was blown away with the clarity of sound.
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Old 15th January 2017, 11:06 AM   #1940
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What load did you have on the output of the AK4396? The caps on the rail are there to reduce the induced rail noise (caused by the internal opamps operating in classAB). But you can also reduce the rail noise by reducing the output loading. So if adding caps blew you away you may find reducing the load (increasing its impedance) gives you a similar enhancement but primarily to the bass (where the caps are having little effect).
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