Question - Amplifier polarity related.

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Question - Amplifier current direction with music.

I am here to learn as much as I can, and to do so, sometimes one must ask what may be seen as a stupid question.

Amplifiers have the + terminal and the negative.

I have assumed that all current flows out of the + terminal and is taken back into the unit through the negative. I have been wondering... Is there actually a push and pull effect going on between both terminals?

Thanks in advance... Gene
 
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You are writing regarding loudspeaker connection.
If the polarity is observed, when a +ve portion of an audio signal connects to the loudspeaker, the cone should push the air out of the cabinet and vice-versa with -ve signal. Blowing and sucking at an audio frequency producing the sound we hear.
If the polarity is not observed and they are opposite, when one speaker "pushes" the other speaker doesn't and a phasing error happens. This makes the sound seem odd, especially with bass frequencies. Try it out and have a listen.
 
What Harleyjon said.

Plus.

The audio signal does reverse polarity during the other half of the complete audio signal.

But if there are the same sounds coming from both speakers at the same time then you want both speakers to push at the same time.

Hence the term "in phase".

The + and - labels are to enable you to hook up both right and left speaker such that this will happen. Speakers will also have either a + and - or red (+) and black (-) terminals.

Harleyjon is right that if you wire one incorrectly it sounds really weird... like the sound is going sideways.

:)
 
Appreciate the answers... But... I realize that the thread title was misleading for what I was seeking... I just retitled the thread.

Yes..I do understand the function of absolute polarity with setting up the speakers. What I really was seeking to find out from those here who would know? With current flowing to and from the speakers from the amp? Does the positive and negative sides actually take turns in which direction the current will flow?

In other words? Does the + terminal itself alternate in pushing out and pulling in current according the the signal being amplified? I wondered if the amplifier is alternating the direction of the current flow with each terminal.

As if putting on the brakes of a speaker transient, effecting the damping factor.

Am I making myself clear? If I am? It still may be a stupid question. ;)

But, its one I never asked, nor seen explained. I have always assumed the + terminal pushed out current, and the negative side always took it back in.

Another reason I asked. One that has intrigued me. If a recording was done with a reversed polarity, the motion of the speakers will be reversed. Yet the terminals at the amplifier is not reversed.

Thanks again... Gene
 
With DC, as in a battery, it's actually the (-) terminal with the excess electron pressure, due to electrochemical dissolution of the anode. The cathode (+) terminal on a battery has a deficit of electron pressure (voltage), so accepts electrons through the circuit when connected. The current flows into the anode (opposite of the electron movement) when the battery is used (discharged)

Presumably, in a AC circuit, the conditions are developed at the amplifier terminals to alternate this condition periodically and drive the speaker inputs accordingly. Whether the speaker moves in or out at the (+) connection is a matter of convention.

Most I've seen move out (towards the listener) when attached to the (+) and (-) terminals as forward polarity, but not all.

John L.
 
The signal is AC alternating current, so yes the current at the terminals alternates. The + and - designations are, from a practical standpoint, fixed to allow consistent connections, so multiple speakers are in phase. A DC offset at the amp outputs will follow the polarity marking, so the amp terminals are largely circuit determined. But a voice coil is an inductor, and inductors don't have a polarity.
 
The signal is AC alternating current, so yes the current at the terminals alternates. The + and - designations are, from a practical standpoint, fixed to allow consistent connections, so multiple speakers are in phase. A DC offset at the amp outputs will follow the polarity marking, so the amp terminals are largely circuit determined. But a voice coil is an inductor, and inductors don't have a polarity.


BINGO! Thanks!
 
No, they don't. A current and magnetic field will create a polarity in the inductor, but just the inductor, no. It isn't polarity sensitive. Relay, solenoid, and loudspeaker coils are given a polarity marking for the same reason - reliable consistent action. It doesn't matter which end is which, for example, in a parallel RL filter on an amplifier output or a CLC power supply filter.
 
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