How many electrons?

(F)Trillions or more.

Actually, on musical peaks it would be well over a million trillion. Not sure what point you are trying to make, though.

Regards,
-- Al

Geoff and Elizabeth, note that the question referred to "the number of electrons that move between the amp output poles and the speaker cables every second, in either direction."

As I interpret it, that clearly refers to the number of electrons moving past a single, specific, fixed location (in either direction) in a given amount of time. That location being either of the two connection points between amplifier and speaker cable (although any other point in the run could be chosen without affecting the answer). Based on that interpretation, my answer is correct.

If the question had been how many electrons travel from one amplifier terminal through the cabling and speaker to the other amplifier terminal, then yes the answer would be approximately zero. But that was not the question, as I read it.

Regards,
-- Al

Lady and Gentlemen,

Expanding on my previous post, the facts that electrons that are moving in response to an ac voltage "don't move much," and "stay very close by their atoms," and have a very slow drift velocity, all of which I agree with, do not change the fact that during each second trillions of electrons will flow back and forth across any given cross-section of the conductor.

Yes, each electron will move an EXTREMELY small distance during each half-cycle of the signal, but nevertheless those trillions of electrons will cross the plane of that cross-section during a given half-cycle, and will then cross it again in the opposite direction during the next half-cycle.

As I said earlier, if the OP was asking about the number of electrons that might make a complete round-trip from amp terminal to speaker and back to the other amp terminal, then I certainly agree that the number would be zero or close to it (my compliments to Geoff for including the word "approximately" in that regard, reflecting the fact that there is always some non-zero degree of randomness in electron movement). And I don't think we can say with certainty what the OP meant, without further clarification from him. But a literal interpretation of the wording of his question, IMO, suggests that the answer is trillions, not zero.

Regards,
-- Al

06-10-11: Hifihvn
Almarg, would the close to it part be do to any resistance?

Elizabeth's subsequent post provided a good answer as to the reason for the "close to it" part:

06-11-11: Elizabeth
The number which would make the round trip might be some whole number, only because of the incredible number involved. So some, just because of random behavior, even though it is VERY unlikely, might just by chance manage the amazing feat.

The number of electrons that are involved, btw, is far larger than the "well over a million trillion" that I mentioned in my first post near the start of this thread. That number referred just to the number of electrons oscillating back and forth across a single cross section of the conductors, over a very short distance. A similar number of different electrons would be oscillating back and forth across every other cross section spaced some small distance apart over the length of each conductor.

06-11-11: Elizabeth
How small a DC offset in volts, would be needed to allow an average of one electron per second to start the round trip from amp output to speaker, through speaker wires etc and back if the total distance traveled is 100ft. and how long would it take the electron, on average?

I don't think that a meaningful answer can be calculated, because drift velocity is proportional to current (see this Wikipedia writeup), and for such a small current drift velocity would become essentially zero.

It should be noted, btw, that the 1 cm/hr figure that has been stated a number of times above will vary widely depending on current. As shown in the example near the bottom of the Wikipedia page, for 3 amps flowing through a 1 mm diameter (about 18 gauge) copper conductor, drift velocity is about 1 meter/hour. 3 amps rms corresponds to 72 watts into an 8 ohm load. A drift velocity of 1 cm/hr would correspond to a current of 30 milliamps in that size wire, which is 7.2 milliwatts into an 8 ohm load.

All in all, I'm starting to think that Bill (Audiofeil) had the best answer :-)

Regards,
-- Al

06-11-11: Shadorne
Stereo speakers run on AC. AC is Alternating Current. Since we use Alternating Current there is no net transfer of electrons to the speaker. (Your speakers are NOT like a car battery that you would charge with DC)

Simply put, if your speakers were being charged and electrons were constantly building up inside them then eventually they would become highly charged like a battery.

Hi Shadorne,

Agreed. I don't think anyone has said anything inconsistent with this.

Best regards,
-- Al

06-11-11: Bifwynne
Hey Al, so . . . you agree with Bill (Audiofiel). What do you have against Carl Sagan (not bifwynne)???

My apologies, Bruce. I should have given that response at least a nomination for second place. My wife has frequently quoted that same Carl Sagan expression, so I guess Bill's analysis struck me as more novel.

Best regards,
-- Al :-)

Shadorne, the statement you quoted from the OP in your last post omits the words "in either direction," which were at the end of the OP's sentence.

None of the rest of us who have responded have interpreted the question as referring to net movement of electrons, or to transfer of electrons to the speaker. And none of the responses, including mine which have referred to the movement of trillions of electrons, have implied that there is any NET movement or transfer.

Best regards,
-- Al