Capacitor positioning

So I came across a youtube video where capacitor orientation was described and it's importance in keeping external noise from getting into a capacitor. It showed examples of older caps that were marked to identify what end was connected to the outer winding which acts as a shield to external noise. It also stated news caps are not marked. And an oscilloscope was used to show what lead was connected to the outer shield. It stated this is important in electrical circuits. Would this be important in crossovers?
 
If we're talking about crossover filters inside of speakers, then no. The impedances are pretty low in speakers so any EM field will have a hard time inducing or coupling any energy into the outer foil of a foil cap.

It's more of an issue in phono stages and (possibly) active crossovers.

Tom
 
So I came across a youtube video where capacitor orientation was described and it's importance in keeping external noise from getting into a capacitor. It showed examples of older caps that were marked to identify what end was connected to the outer winding which acts as a shield to external noise. It also stated news caps are not marked. And an oscilloscope was used to show what lead was connected to the outer shield. It stated this is important in electrical circuits. Would this be important in crossovers?

Audio signal is ac, current goes back and forth. Ground and live signal are just mental images.
So is signal path.
No such thing in real world.
 
"The proper way to connect the outside foil is to the low impedance side of the circuit, which, in the case of coupling caps, will normally be the plate of the previous stage. If it is a bypass cap to ground, connect the outside foil to the grounded side. If it is a bypass cap from a signal to B+, connect the outside foil to B+. The outside foil will act as a shield against electric field coupling into the capacitor, so you want it to have the lowest impedance return path to ground."
https://www.aikenamps.com/index.php/where-to-connect-the-outside-foil-on-capacitors#:~:text=If it is a bypass cap to ground,,have the lowest impedance return path to ground.

May apply to valve amplifiers, but not to crossovers.