[Cecala]

I'm building the Sigma22 PS and have to pick between Panasonic FC series and Nichicon capacitors(Various series). I need opinions from knowledgeable people about which is superior. Please state reasons in detail.

 

[tomb]

Quote:

Originally Posted by Cecala /img/forum/go_quote.gif I'm building the Sigma22 PS and have to pick between Panasonic FC series and Nichicon capacitors(Various series). I need opinions from knowledgeable people about which is superior. Please state reasons in detail.

You might do what the rest of us do: look up the impedance and ripple ratings in the DigiKey and Mouser catalogs and compare. Surprisingly, you may find the Nichicon UHE caps are better rated than the UPW's or FC's. Of course, a Panasonic FM beats all of them unless it's not available in the size desired, which I'm assuming is the case from your question.

 

[fordgtlover]

Of the 'common' caps recommended by AMB, based on a 50V 150uf cap, it appears the order is

Nichicon pw
Nichicon he
Panasonic fc
Panasonic fm

 

[tomb]

Quote:

Originally Posted by fordgtlover /img/forum/go_quote.gif Of the 'common' caps recommended by AMB, based on a 50V 150uf cap, it appears the order is

Nichicon pw: 0.162 ... 615
Nichicon he: 0.12 ... 760
Panasonic fc: 0.119 ... 850
Panasonic fm: 0.042 ... 1170

Yes - just to make sure, because the order of your post confused me - your list is worst to best, top to bottom. The FM's are significantly better at 0.042 ohms impedance (lowest) and 1170ma ripple current (highest).

 

[Cecala]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif You might do what the rest of us do: look up the impedance and ripple ratings in the DigiKey and Mouser catalogs and compare.

Thanks to all for your responses. BTW Tomb, yes I could look up the above catalogs and so on to find info that I require. Although by posting my question I might reduce my workload, especially something as tedious as looking at fine print in catalogs and benefit from work already done by others-such as yourself.

 

[fordgtlover]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif Nichicon pw: 0.162 ... 615 Nichicon he: 0.12 ... 760 Panasonic fc: 0.119 ... 850 Panasonic fm: 0.042 ... 1170 Yes - just to make sure, because the order of your post confused me - your list is worst to best, top to bottom. The FM's are significantly better at 0.042 ohms impedance (lowest) and 1170ma ripple current (highest).

Sorry. I should have been clearer in stating that the list was worst to best. Cheers Tomb.

 

[n_maher]

Given the measured (by amb) ripple on the output of the sigma22 using the "worst" upw's I think it's safe to say that they're doing their job just fine. If you want to use better rated caps just be aware that you've crossed a performance threshold that borders on absurd.

 

[tomb]

True enough, Nate - except that the Panasonic FM's are cheaper than UPW's - cheaper than FC's by a long shot. Only the UHE is cheaper in the size we've been talking about in this thread and only by 1 cent (DigiKey prices).

 

[LawnGnome]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif True enough, Nate - except that the Panasonic FM's are cheaper than UPW's - cheaper than FC's by a long shot. Only the UHE is cheaper in the size we've been talking about in this thread and only by 1 cent (DigiKey prices).

Your saying the Panasonic FM's are cheaper than the Panasonic FC's?

The FM's are much better. I use quite a bit of them.

Another good series is United Chemicon KZE. Quite cheap.

 

[amb]

The minor difference in specs notwithstanding, I basically treat the Panasonic FC, FM and Nichicon UHE, UPW series as equivalents for PSU rails. Which one I use is determined more by the availability in a specific size (diameter, pitch and height for proper fitment), and which vendor I'm also ordering parts other parts from.

 

[budx3385]

what about the Elna for audio series?

 

[tomb]

Quote:

Originally Posted by LawnGnome /img/forum/go_quote.gif Your saying the Panasonic FM's are cheaper than the Panasonic FC's?<snip> ...

YES - that's been my argument. Their ratings are better than FC's and UPW's, and then to sharpen the point, they are cheaper, too. The only caveat to using Panasonic FM's is what Amb mentions - the line is not as extensive as FC's or UPW's. FM's only go to 50V, for instance, and smaller ratings are not available at low voltages, either.

Quote:

Originally Posted by budx3385 what about the Elna for audio series?

"For audio" is the key. We've been talking about caps in a Power Supply outside of the signal path. "For audio" usually implies a cap that's sufficiently tonal in quality that it can be placed in the signal path without sounding bad. Outstanding power caps such as the Pana FM's can often sound harsh in the direct signal path. However, "audio caps" - including the Elnas - do not have impedance and ripple current ratings that are as good as the Panasonic FM's.

That said, some have pointed out that the voltage in the power circuit ends up in the signal path, anyway. So, a case can be made that an audio cap might be appropriate in a power supply despite ratings that are not quite as good. It depends on the particular amp design whether an audio cap would be of benefit vs. a power cap of better ratings such as the FM.

Amb's B22 is good enough in this instance that none of these issues come up. He has said that any of the caps mentioned will provide excellent performance and you can bank on that. The Elna's would probably be OK, too, but you will have paid a huge price to make no difference. IMHO and YMMV x10

 

[Seaside]

If I have to list them according to my personal preference, it would be ... HE, FM, PW, FC. Your preference may differ from mine. At least, they all are good for PSU positon.

 

[dsavitsk]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif "For audio" is the key. We've been talking about caps in a Power Supply outside of the signal path. "For audio" usually implies a cap that's sufficiently tonal in quality that it can be placed in the signal path without sounding bad.

Tom, you like to say this, but I think it is simply not true. Everything is in the signal path. It is true that some circuits, particularly solid state circuits, have good PSRR, but the ripple and noise that is rejected is not necessarily linear. So, just because an opamp, for example, can reject 60Hz or 120Hz noise, it does not mean that it can reject HF or even audio frequency noise. Certainly some circuits are better than others, and it may be that Amb's circuits are so good that the quality of the caps is unimportant, but in many other instances, the quality of the power supply cap matters a lot.

Here's Lynn Olson's explanation of how the PS caps are in the circuit path.

And, to add my thoughts a little, I once did a little cap listening experiment where I used a "cmoy" type circuit as a gain stage for a DAC (The DAC usually uses a tube gain stage and sounds very good.) I settled on two different opamps (OPA637 and AD843), and tried a whole series of electrolytic caps right on the power pins (bypassed by 0.1uF stacked foil caps which surely influenced the sound). Differences in sound were, in some cases, as large as switching opamps. Also, I didn't do any extensive burn in as I was too lazy. The basic results from best to worst were as follows (and notice there is lots of stuff I didn't try):

1. BlackGate N series -- these just sound good -- clean and clear and full
2. Elna Cerafine -- also clean and clear, maybe a touch worse than the BG N, maybe not. Good choice if you can get them.
3. United Chemi-Con NPCAP (These are more or less like OSCONS) -- not quite as full as the ones above, but pretty good, very smooth.
4. BG Std -- clean and clear, but maybe a little thin sounding.
5. Nichicon Muse KZ -- a little hard on top, but only a little.
6. Elna Silmic -- These sound a little hard to me, but detail and speed is good.
7. Panasonic FM -- nice full warm bass, but missing something in the treble. Seem a little noisy on top too.
8. Panasonic FC/Nichicon UPW -- I think there is a pretty big drop off to either of these. Hard and unmusical sounding -- only useful for breadboarding.

As I say, different circuits are going to behave differently, but at least for a simple opamp, this is what I found.

 

[tomb]

Quote:

Originally Posted by dsavitsk /img/forum/go_quote.gif Tom, you like to say this, but I think it is simply not true. Everything is in the signal path. It is true that some circuits, particularly solid state circuits, have good PSRR, but the ripple and noise that is rejected is not necessarily linear. </snip>

Gee, Doug - fair enough I suppose, but I'm not the only one that says it - and it's a well respected opinion. Maybe you didn't see my next paragraph above after I said that:
Quote:

Originally Posted by tomb That said, some have pointed out that the voltage in the power circuit ends up in the signal path, anyway. So, a case can be made that an audio cap might be appropriate in a power supply despite ratings that are not quite as good. It depends on the particular amp design whether an audio cap would be of benefit vs. a power cap of better ratings such as the FM.

So - not as useful as your info, for sure - my opinions never are - but I did say it. I also agree that perhaps the simpler the circuit, the more effect these caps will have. Nevertheless, you ended up saying the same thing: the Panasonic FM's are much better than FC's and UPW's. Since they're significantly cheaper in many sizes, it's a no-brainer from my perspective.

Anyway - thanks for your capacitor opinions as always - I always enjoy reading them and learning something else.