Best electrolytic capacitors

[Kurt von Kubik]

You can make the cap bank much faster by using 2 planes for plus and minus - this creates a low inductance bus connection to the caps, see Rifa's "Electrolytic Capacitors Application Guide" page 5 http://www.evoxrifa.com/electrolytic_cat/electrolytic_appguide.pdf



I think there are two points to consider:

1. Being magnetic the skin depth of Steel is very low, about 1/38th that of copper (from a WEB article, but you should be able to calculate this for yourself if you mistrust the figures). At DC the conductivity of steel is ok, ca. 1/7th that of copper. But with rising frequency it will quickly stop conducting at all, so the impedance is not linear. In coupling caps I would consider this as no-no, as a power supply cap it "may" actually be ok. Actually I just got some non-polar caps that unfortunately turned out to have magnetic leads, I might do some listening tests to see how they compare to other caps (caveat is that I do not have the same caps with copper leads).

2. The measured distortion was referenced in a Nichicon article but I couldn't find it on the WEB. I still have a 2 page copy from an article but without a reference to point you to. One ould have to measure similar caps with and without steel leads to get a better picture, but then why take a risk if there is a potential of added distortion.

I am not sure if the same mechanism would actually apply to enclosures but at least one point should be critical, and that is eddy currents of signal carrying wires which may just be worse in steel enclosures. I would keep all signal leads away from metal surfaces anyway as I do believe this could otherwise cause audible distortion (you might actually be able to measure this ?). Note also that a couple of manufacturers, including Brinkmann, use metal enclosures except for the top plate, claiming that this makes a noticeable difference, some others do not use any metal at all (see DNM Design WEB pages for their principles). This would be similar to what Kenwood were doing.

Steel leads on caps are mostly copperclad, which is steel covered with copper and lastly they are tinned. That makes them excellent for high frequency use. Copper would of course be better @ DC, but you ought to condiser the lengt of the leads when soldered in place, and also the conductivity of both the solder and the very thin PCB lanes.
IMHO they do not ad anything substantial to the sum of all resistances.
Radial electrolytic caps for soldering will rarely be used for smoothing, because they come mostly in smaller values, if they do, often several paralelled will be present, which practically eliminates the problem. Decoupling would be where I´d use them.
For coupling no cap is good, IMHO they should be avoided regardless of type.

 

[nortonl]

Output cap reccomendations ?

I need to replace the output coupling capacitors in a Leak Delta 70.

The originals are 50v 2200uF polarised electrolytics. I have heard that increasing the value to 4700 or 10000uF might be a good idea especially since modern items are smaller.

Obviously electrolytics in the signal path are not ideal so I would appreciate any recommendations for the least bad option in this application.

Thanks.

 

[Kurt von Kubik]

Large values with good coupling properties are hard to find.
Elna Silmic stops @ 1.000µF unless the 50V are somewhat overestimated.
50V will indeed give a lot of power @ 8 Ohms, so if a lower voltage is suitable, I´d go for the Silmics paralelled by an Evox SMR polyphenylene sulfide capacitor or similar.

Just my 5 cents

 

[nortonl]

Tested today and measured 35V on the input side of the cap. The psu is a single 75v rail so I guess that explains it.

So yes 50V is needed.

I might be able to get a pair of 2200uF Black gates.

I guess the best solution would be a transformer instead of a cap but I've never seen any suitable for this application.

Any other suggestions ?

 

[martinbls]

What about a cap that wasn't mentioned yet in this thread, the Panasonic TS-HA for smoothing in amp power supplies?

It's used for example here (paralleled with some Panasonic FC's):
hoer-wege Mono-Endstufe AMP 1

And recommended here:
DIYCable.com : Intro » Home » Exodus/Hypex Amps » Amp Parts »

Datasheet:
http://www.diycable.com/main/pdf/tsha.pdf

Any comparisons of these with, say, BC Components, SlitFoils or Mundorfs?

 

[MRupp]

IMHO they do not ad anything substantial to the sum of all resistances.

The resistance as such is not my concern but rather the change over frequency, and that in the audio band. Admittedly, due to the small wire length this may not be audible (you would have to compare versions of the SAME cap with steel and with copper wire to be conclusive). BTW, this is Nichicon document I was refering to earlier, once posted by Charles Hansen, though I couldn’t find a version at the Nichicon pages:

That makes them excellent for high frequency use

I am aware that silver over copper plated steel wire is used in HF conductors. The following is anectdotal: Some time ago I needed longer interconnects (1.5m). German HiFi magazine Stereo had an article about a “giant killer” DIY interconnect cable, RG 142 B/U, coax with silver over copper plated steel core and Teflon insulation. I built a pair, with bullet plugs, to connect preamp to poweramp. Despite my anticipation the cable sounded very unpleasant. For example, pieces of information seemed to have gone in the upper bass region, with some classic music I felt that instruments had miraculously disappeared. I gave it a few weeks just to see if it would “break in” , but to no avail. Finally I replaced it with a standard Kimber cable and the sound was IMMEDIATELY back to normal. I do not make listening comparisons between cables very often but the difference in this unforeseen test was night and day.

 

[JJFK]

What do you think of Sanyo WG capacitors?

 

[umut1001]

High End Audio - Electrolytic capacitors Here the test and it says Elna is better than most at most applications.But i see that people often use panasonic fm caps in diyaudio.com. I think elna is great for signal path but panasonic seems have more much current than elna.What about this subject? Smooth filtering ? Is it really an important thing for power supply of a preamp?what is more important? smooth filtering or high current ripple?

 

[Telstar]

High End Audio - Electrolytic capacitors Here the test

Nice test. I hope Eric will add the FM and the OS-CONs soon.

 

[Eric Juaneda]

I hope Eric will add the FM and the OS-CONs soon...

I have three Panasonic FM in a box, but never test it. They have smaller size than Panasonic FC. I don't think they could sound better. I never made comparison, it's only a supposition.

Many people have tried OS-CONs. It seems to be a very good cap for digital, not so good for analog. OS-CONs have very small tension values <35V. I can't integrates it in my test.

It would be more interesting to try Nichicon KZ or Nichicon KW who are audio grade capacitors like ELNA or Black Gate.

 

[bobodioulasso]

I like these(obsolete) por PSU.

 

[Telstar]

I have three Panasonic FM in a box, but never test it. They have smaller size than Panasonic FC. I don't think they could sound better. I never made comparison, it's only a supposition.

Hi Eric!

I really suggest you do, since I have heard people rate them as the best black gate replacement, and higher than the FC (i.e. on head-fi and also here), and considering the price they seem a best buy to me.

It would be more interesting to try Nichicon KZ or Nichicon KW who are audio grade capacitors like ELNA or Black Gate.

That would be interesting too

 

[ClaveFremen]

I have three Panasonic FM in a box, but never test it. They have smaller size than Panasonic FC. I don't think they could sound better. I never made comparison, it's only a supposition.
...
It would be more interesting to try Nichicon KZ or Nichicon KW who are audio grade capacitors like ELNA or Black Gate.

You should do, FMs are much better than FCs soundwise, less harsh and more refined (but with a not well controlled bass).

If you try KZs dont't judge them without a 100 hours burn-in, at first they're closed and sounds too 'big'.

 

[Nazar_lv]

It would be more interesting to try Nichicon KZ or Nichicon KW who are audio grade capacitors like ELNA or Black Gate.

Nichicon KZ is better than Elna Cerafine/Silmic/Silmic2 BG FK, and after electrotraining better than Panasonic PZ/PXL

 

[Variac]

Nelson Pass seems to be a big fan of Silmic ll's

 

[event horizon]

There's hemp in them, too.

I guess when the capacitors finally give up, leak & possibly smoke it's best to be breathing deeply above the amplifier or whatever

My bad, apologies but i couldn't resist it Hemp will give you a headache anyway

On a more serious note i like BHC ALS caps for power supplies

 

[bobodioulasso]

"So all this talk of saving planet Earth, well that's not the problem. Planet earth doesn't need saving, it's a great survivor. It's not the planet we should be worrying about, it's us!"

More than us only but the whole living.

 

[tomat]

Hi BoBo
How are you? are you in the forest at this moment?

 

[tomat]

You should do, FMs are much better than FCs soundwise, less harsh and more refined (but with a not well controlled bass).

If you try KZs dont't judge them without a 100 hours burn-in, at first they're closed and sounds too 'big'.

Hi
i was replace cathode bypass capacitor in my tube preamp from BG Fk to nichicon muse KZ,without waiting much time,they sound better than FK,more clear & transparent

 

[bobodioulasso]

Hi BoBo
How are you? are you in the forest at this moment?

Hi Tomat
Nice to read from you.
Its raining in my forest and i feel like this little frog of my avatar.