Capacitor orientation questions

[darren01]

Hello,

Please forgive my basic capacitor questions. I am a newby.

I am informed that with common ployproprolene capacitors there is a way to correctly orient them in the signal path. Meaning, passing the signal through it on one particular side is better than the other.

I understand the concept but do not know how to go about finding how to determine which lead to orient as the source and the output.

Can this be done with a simple multimeter?

Thanks in advance.

Darren

 

[peranders]

Can you please give me good references for this important discovery?
.... not very true.... unless you have good proofs.

 

[fmak]

Can you please give me good references for this important discovery?
.... not very true.... unless you have good proofs.

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This is well accepted; for ex, the direction of the outer foil and whether this is grounded makes a difference.

The simple thing for you to do is to try it.

 

[peranders]

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This is well accepted; for ex, the direction of the outer foil and whether this is grounded makes a difference.

The simple thing for you to do is to try it.

Have you tried to have a safety pin in the curtain?

If you have made like a roll, which foil is the outer?

Sorry fmak, I don't believe this very much... but it's very important to orient all resistors so the tolerance ring is toward the signal. I have also discovered that it's very important to have the resistors orientent in east-west direction.

 

[Freddie]

but it's very important to orient all resistors so the tolerance ring is toward the signal. I have also discovered that it's very important to have the resistors orientent in east-west direction.

Ohh no Never thought about that, now I have to rebuild my QRV06 headphone amp

/Freddie

 

[dhaen]

Bands on the run

It makes sense to connect the outer foil to the low voltage point (closest to chassis potential. In fact I learned it at college, way back. At that time all non-electro caps had an outer foil band marking.
Whether it makes any difference in terms of signal quality; I doubt it.

 

[fmak]

Have you tried to have a safety pin in the curtain?

If you have made like a roll, which foil is the outer?

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I don't know what your are talking about. As I said, why object if you are not at least prepared to try and listen.

Do not approach engineering and science with Predetermination

 

[Tony Salsich]

If I may offer my two cents worth:
The outer winding of the cap is sometimes referenced with a band near the lead to which it is connected. The two purposes, as I was taught, are (1) to allow the designer to place that winding's surface nearest to its reference potential; and (2) to allow for 'backstrapping' the cap for lowest possible inductance. The former allows one to avoid potential breakdowns in the outer insulating layer in case of physical damage, while the latter can only be fully realized by connecting the cap to the circuit in an unconventional way.

Picture sliding the cap into a tight fitting, metal cylinder. Now add an end plate to the cylinder and the lead connected to the inner foil. You would then have a coaxial capacitor that yields lowest stray inductance, provided that you provide a ring connetion to the cylinder at the end nearest the outer foil.

I hope that I got the idea across. BTW: this connection may provide unnoticable results in audio circuits.

Tony

 

[KBK]

but can count in tube curcuits where the mass considerations make the capacitor's behaviour more critical. meaning: less mass, so the cap's own mass response characteristics become more of an issue.. and the voltages can be rather high - as an additional or conjunctive issue.

 

[Peter Daniel]

Check this post by Jonathan Carr describing how to find an outer foil http://www.diyaudio.com/forums/showthread.php?s=&postid=121850#post121850

Also, few posts earlier, Bobken presents his method for "sexing caps".

There is no question about the observation that caps sound different, depending on orientation. The question is which way to choose. I usually go with the outer foil directed to the output, it seems to sound smoother and more coherent.