Where To Connect the Outside Foil on Capacitors

[xtian]

After seeing yet another TW with bands marked on the film capacitors, I wanted to know the whys and hows. Aiken has an excellent article:

Where To Connect the Outside Foil on Capacitors
http://www.aikenamps.com/OutsideFoil.htm

Wondering if you have any comments on Aiken's article, or on the practical, real world effects of outside foil orientation in your builds.

[xtian]

I tried Aiken's method of detecting the outside foil lead with a scope. Turns out to be very easy for caps 0.1uF and under, and quite obvious.

[vibratoking]

To be honest, I hear little to no difference. Others hear a big difference. For instance, many have said that certain Dstyle amps are not friendly to Strats, especially in OD mode. I agree with this. Gil Ayan has stated that capacitor orientation will make those amps more friendly to Strats in OD mode. I tried it both ways in my 183ish build, but I didn't notice any difference. Wish I did.

Not trying to be offensive to anyone. Just stating my experience. I often have different experiences than others with respect to things like this.

[eniam rognab]

hey thanks for linking that

good stuff, brain food

i have "heard" that its best for the signal to go into the inside foil and exit on the outside foil. i also "heard" that it doesnt matter which orientation they are as long as they are the same throughout.

(grain of salt needed)

[xtian]

Aiken is clear in his article that this is about shielding your circuit from noise, not about influencing the tone. I'm not interested in snake oil tone recipes, but I am definitely interested in keeping noise down in my builds.

[Cliff Schecht]

You want the outer foil of the capacitor facing the lower impedance side of the circuit. Whether the lower impedance is a ground connection or the output of a tube stage, the lower impedance will in theory be able to shield more effectively. I'm with VK in that I've never really noticed a difference though..


Edit: just browsed the article and Aiken agrees. Whether you are dealing with AC or DC grounding, the outer foil goes to whichever side has the lowest resistance (or impedance if a cap/inductor is involved giving you a real and imaginary component).

[10thTx]

Some very useful information & photos, video here:

http://www.el34world.com/Forum/index.php?topic=11427.0

With respect, 10thtx