If it is still rated for the amount of voltage and amperes required to flow through it, then I don't think the quality would matter.
That said, there usually isn't a ground in an AC output system; it is fed back to the transistors in the amplifier.
Those transistors are fed by some DC rails (likely), but often well-above and well-below ground potential on both sides at all times (usually).
i.e. Neither AC nor DC requires a ground to function.
In any case... I don't think the power supply or output transistors will really "care", since any power not converted to radiation in the voicecoil and XO's and speaker cables is always returned to the same source regardless.
Technically... there is no such thing as particles. Only waves and fields of potential energy with state information (which interact with each other).
Relativistically, they are at all-possible potential states relative to an observer in a different space-time frame of reference. i.e. the EM waves and electrons took all paths through the circuit at the same time, instantly (from its perspective or without observation.)
In this case: based on the mechanical properties of the crossover, the information system collapses into a single state based on the electrical properties of the system, and any given electron only takes one path in the parallel circuit (especially so, when we try to observe it...) [The EM fields take all paths, but are attenuated or manipulated accordingly.]
Electrons have a charge / polarity, and they move in a closed loop around the nuclei, based on fields-of-force (strong-force, weak-force etc). But at no point were they particles.
When these fields of charge move through a conductor, EM fields are generated, which in the case of a woofer oppose the magnetic fields of the permanent magnet (which is a solid, with electron-locked polarities in a cluster).
Thus the cone moves away from these opposing fields and air is pumped, making sound.
A "solid" is merely a (tightly packed) temperature-locked cluster of fields and waves. Nothing more.
Everything you were taught about particles is mostly a lie, and dark matter theory proves the ineptitude of their classic model.
The universe doesn't operate on a million different oversimplified equations. That's where they went wrong!
It ONLY operates on a single unified field equation that takes ALL relevant information-states and field-types into account SIMULTANEOUSLY (including spooky-action and all the laws of motion, heat, energy-transfer and gravity within-and-without a blackhole [and any other: place, time or "thing"....])
Nobody said it was "gonna be easy" or "had to be easy" to function the way it clearly does.
The behavior at the quantum level IS different from the macro level. But not in the way you'd expect
/ were told.
The observed complexity INCREASES as the scale DOES, it doesn't
get simpler. LOL That's again where they are WRONG. It is the SAME equation but expressing
ADDITIONAL levels of complexity at-scale.
A cluster of electrons have a different resultant than a single unit does.
Such as friction, and spring effect; those aren't found [easily] at smaller scales, but the SAME laws/equation is at play in all cases. (i.e. Consistency
-My 2 cents