A small Doubt regarding headphone jack

[Nitin]

I was wondering whether DC current flows or AC current flows from a
headphone Jack. I am not sure because I was reading articles which were
saying to measure the DC voltage between the Left and the right channel
with respect to the ground.
My question is how can a speaker produce varying output if DC current
comes out of an Headphone jack.
Please help me in clarifying my doubts. I am using the output from my
PC sound card.
Thanks
Nitin

 

[Tony Martinez]

I was wondering whether DC current flows or AC current flows from a
headphone Jack. I am not sure because I was reading articles which were
saying to measure the DC voltage between the Left and the right channel
with respect to the ground.
My question is how can a speaker produce varying output if DC current
comes out of an Headphone jack.
Please help me in clarifying my doubts. I am using the output from my
PC sound card.
Thanks
Nitin

DC FLOWS FROM THE HEADPHONE JACK BECAUSE IF IT HAS A 1/8 PLUG THERE'S A
GOOD CHANCE THAT IT IS BEING POWERED BY A BATTERIE.

 

[Bob AZ]

Not hardy. The speaker is an AC device. It may have a DC quiescent
current but responds to AC at the frequency of the audio signal

Bob AZ

 

[Lars Goldschlager]

I was wondering whether DC current flows or AC current flows from a
headphone Jack. I am not sure because I was reading articles which were
saying to measure the DC voltage between the Left and the right channel
with respect to the ground.
My question is how can a speaker produce varying output if DC current
comes out of an Headphone jack.
Please help me in clarifying my doubts. I am using the output from my
PC sound card.
Thanks
Nitin

The detail here is that the current in a headphone jack will vary, to
produce the vibrations in the headphone's cone/membrane, to reproduce
sound. But, unlike what some people consider AC current:

A) The variation is not a stable wave with a periodic variance over time.

B) Current varies between little or no flow, to a certain degree flow in
one direction. "AC" current varies between one direction (polarity,
charge) and the opposite, that is, it's state shifts between positive
and negative flow.

 

[Sam Goldwasser]

Not hardy. The speaker is an AC device. It may have a DC quiescent
current but responds to AC at the frequency of the audio signal

And significant DC current is a common way speakers get fried due to
a defective amplifier.

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