Output polyprop caps 10 uF - orientation

[fritzthecat]

Hi there

I am just rechecking my work at the moment before I do the final turn on (my heart is already bumping as if it wants to jump out of my chest) followed by the necessary adjustments (hum balancing - hope I get there - keep fingers crossed...) when a question popped up in my mind:

Is it in any way important soundwise how the output polypropylene caps are oriented (I am talking about the Solen 10uF caps that have to connect between 36u-56u and 42u-62u // and of course the same question popps up again thinking of the 0.1uF input caps).

VCap for example mentions this on their website that it is crucial wheter the input side is connected to the outer or the inner foil of their caps. I think Audio Note recommends the same as well regarding their tin-, copper-, and silverfoil / mylar foil in oil capacitors).

Does anyone have experience regarding this? Are there any general recommendations from Bottlehead's product development side?

Is there a theory available?

Is anyone able to advise how to properly orient them for best results or doesn't it matter at all? And in the end: how do I find out which lead connects to the inner foil and which to the outer one?

I am very curious to find out wheter this is just a "Voodo" thingy or proven fact to be important? And if, what's behind it in terms of physics?

I am very interested to get some input and/or opinions regarding this as I am planning to build a real custom Kaiju with my second kit (should have waited for the custom kit that just has been announced - it looks great but I guess there is mor or less the same parts insid. I'd love to build a "Swiss Edition Signature Kaiju" but therefor I really need further advice to get the very best results at the end.

Thank you so much - it's great being in here - very positive experience for me and the only thing I can do so far is to give the candidate the full 100 points! Bottlehead and the Forum both is just great! Thanx a lot! I never felt that comfortable building kits before!

 A nice weekend to everybody!

Chris

[kgoss]

Just orient them the same way and enjoy the music. I install the same direction that the manual shows. The outer foil isn't marked on Solen caps but if you want to learn how to identify it just search the forum. This subject comes occasionally.

[drewh1]

Different cap manufacturers seem to have different specs.  I followed vcaps recommendations for vcaps. Mundorf does not seem to have polarity so I positioned both in the same orientation using the printing on the cap. I would use the orientation shown in the manual for the solens 

[mcandmar]

The only way i know to determine the inner and outer foil of a capacitor is to connect them to an oscilloscope, but its really splitting hairs and not worth worrying about to be honest.

[Paul Joppa]

The only theory I have ever heard is that the outer foil can pick up noisy electric fields more easily, since it shields the inner foil. The resulting noise is most easily drained to ground if the outer foil is connected to the lowest impedance, which is usually the source. So it's good practice to connect that way if you can. But the effect is quite small, and the signals in a power amp are quite large, so it is very unlikely to be an audible effect in a power amp.

Note that a 300B has about 700 ohms plate resistance, and the 10uF cap has about 300 ohms reactance at 50Hz, the lowest frequency noise field you might find typically. At higher frequencies the reactance is even smaller. So the parafeed output cap will easily drain noise from either end.

[fritzthecat]

Hello everybody

thank you for the replies - I have to read everything again and do some research to make up my mind. Lucky me, I oriented the Solen Caps the way shown in the manual.

All the best and have a great day,

Chris