Electricity regardless of hf, lf or mf travel at the same speed (almost the speed of light). It can travel 7 times across the globe in a second. The only thing that changes with frequency is the wave length of the wave. Electrons however travel much much slower. They travel at what is known as the drift velocity and travel slower than even a snail. The drift velocity of electrons through a copper wire of cross-sectional area 3.00 x 10-6 m2, carrying a 10A current, is approximately 2.5 x 10-4 m/s, or one-fourth of a millimeter per second. If ever the electron reaches the speaker coil from the amplifier, it will be a miracle. But then how does electricity travel if electons are so slow? It travels like a wave. It is like standing in a long queue with no space between the people. The person at the end pushes, the effect of which will be felt almost immediately by the person at the front of the queue.
The speed at which the signal reaches the speaker is the signal velocity which is the same for hf, lf or mf. Once it reaches the coil, the movement of the coil moves the diaphragm and this produces sound. It's after this stage you may get a difference because no speaker is perfect. If you have multiple drivers, the distance of each driver from the ears, cabinet construction, acoustic lobing, reflection, etc will determine if all frequencies reach your ear at the same time or not. That's my understanding and the thing this different plating on the base conductor will do is attenuate the high frequencies differently (skin effect + electrical resistance of the plating).
However, different frequencies have different attenuation is explained here
If I arranged an experiment where light raced electricity what would be the results? Let's say a red laser is fired at the same time a switch is closed that applies 110 volts to a 12 gauge loop of ...
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Imagine Usha Uthup singing with her deep throaty, manly low frequency voice and a person playing guiter, violin, cymbals. Another person playing the drums.
Imagine the havoc if the guitar, violin, cymbal sound reach you earlier, followed by Usha Uthup's voice and in the end the drum beats totally out of tune.
Even in air, sound HF, LF or MF travel at the same speed.