You have a problem with the concept of watts.
Watts don't flow through a resistance. Only current flows.
Watts are dissipated (as heat) in a resistance and can be calculated by: Watts = Current x Voltage
With 8 volts and one 8 ohm speaker the current flow through the speaker is 1 amp. The entire 8 volts is across the speaker so: Watts = 1 x 8.
With 8 volts and two 8 ohm speakers in series the current flow through the speakers is only 1/2 amp because the resistance is doubled. The voltage across each speaker is 4 volts.
Apply the formula to either of the speakers: Watts = 1/2 x 4. The result = 2 so each speaker is dissipating 2 watts.
If you wire more speakers in series the current decreases even further and the voltage seen across each speaker is less:
the total voltage/number of speakers = the voltage across each speaker.
With 10,000 8 ohm speakers wired in series, the current flow with 8 volts applied will be 8/80,000 which is .0001 amps. The voltage measure across each speaker will be .0008 volts. The power dissipated by each speaker will be .0001 x .0008 which equals .00000008 watts.
Clear as mud isn't it?
Watts don't flow through a resistance. Only current flows.
Watts are dissipated (as heat) in a resistance and can be calculated by: Watts = Current x Voltage
With 8 volts and one 8 ohm speaker the current flow through the speaker is 1 amp. The entire 8 volts is across the speaker so: Watts = 1 x 8.
With 8 volts and two 8 ohm speakers in series the current flow through the speakers is only 1/2 amp because the resistance is doubled. The voltage across each speaker is 4 volts.
Apply the formula to either of the speakers: Watts = 1/2 x 4. The result = 2 so each speaker is dissipating 2 watts.
If you wire more speakers in series the current decreases even further and the voltage seen across each speaker is less:
the total voltage/number of speakers = the voltage across each speaker.
With 10,000 8 ohm speakers wired in series, the current flow with 8 volts applied will be 8/80,000 which is .0001 amps. The voltage measure across each speaker will be .0008 volts. The power dissipated by each speaker will be .0001 x .0008 which equals .00000008 watts.
Clear as mud isn't it?
Watter "is" current
Pressure "is" voltage
Power is water times pressure. 🙂
One stream falling a long way has the same power as 10,000 streams falling a short way.
Can't jam the same water through both. But they can have the same amount of power.
I'm sure I'm being hard headed, but I still don't get it. I understand what you've said, but the why just doesn't gel.
The examples appear to be apples and oranges and theory only. I find it hard to believe that you can apply 10,000 watts of power to a series of 10,000 1 watt drivers. Whether it's 1 volt and 10,000 amps or 10,000 volts and 1 amp , it doesn't seem important. The VC on the first driver is going to fry. Right or wrong? Isn't it irrelevant that the first driver is only going to use 1 watt of the power. How is the other 9,999 watts going to travel through it without burning it up?
Let's take another example. 100 extension cords rated for 3 amps. In parallel they have no trouble with 300 amps total or 33,000 watts. Plug them together end to end and they can't handle that much power. Isn't that correct? or is it that they can handle 3 amps at 11,000 volts ?
The reason I bring this up is I had an array of 12 20 watt drivers. 3 parallel groups of 4 series 4 ohm drivers. I figured 12x20=240 watts. The drivers on the ends of the series groups were getting burned out using a 40 watt/ch amp which was never driven hard. It didn't happen in every group, but the only ones fried were on the end of a series group.... Why?
The examples appear to be apples and oranges and theory only. I find it hard to believe that you can apply 10,000 watts of power to a series of 10,000 1 watt drivers. Whether it's 1 volt and 10,000 amps or 10,000 volts and 1 amp , it doesn't seem important. The VC on the first driver is going to fry. Right or wrong? Isn't it irrelevant that the first driver is only going to use 1 watt of the power. How is the other 9,999 watts going to travel through it without burning it up?
Let's take another example. 100 extension cords rated for 3 amps. In parallel they have no trouble with 300 amps total or 33,000 watts. Plug them together end to end and they can't handle that much power. Isn't that correct? or is it that they can handle 3 amps at 11,000 volts ?
The reason I bring this up is I had an array of 12 20 watt drivers. 3 parallel groups of 4 series 4 ohm drivers. I figured 12x20=240 watts. The drivers on the ends of the series groups were getting burned out using a 40 watt/ch amp which was never driven hard. It didn't happen in every group, but the only ones fried were on the end of a series group.... Why?
The example is extreme, but you chose the numbers. IIRC, some christmas tree lights use 12 V lamps, and series 10 of them together. Works every time.
Wrong. 🙂
Bad Example. Extention cords work because the resistance of the cord is small relitive to the load. put 100 in series, and you violate that assumption.
We build models of the world based on our experience, our training and what we learn from others. Since you have an example where you have observed a contradiction, it will take time. My sugestion is to get a VOM and some resistors and a 12V supply and see how series/ parallel connections behave with "ideal" resistors.
Good Luck.
Doug
johnincr:
Again, it's the confusion with watts. You don't apply watts to a circuit. You apply volts.
Watts don't flow through anything. Only current flows.
So, you apply volts, current flows and power is dissipated. End of story.
So when you use terms like, "watts travel through", or "apply x watts", it is incorrect usage.
Regarding your 3 x 4 array of 4 ohm drivers; it's just a coincidence that end drivers burn out. An end driver is no more likely to burn out than any other. The fact that any are burning out means simply that you are overdriving them.
Again, it's the confusion with watts. You don't apply watts to a circuit. You apply volts.
Watts don't flow through anything. Only current flows.
So, you apply volts, current flows and power is dissipated. End of story.
So when you use terms like, "watts travel through", or "apply x watts", it is incorrect usage.
Regarding your 3 x 4 array of 4 ohm drivers; it's just a coincidence that end drivers burn out. An end driver is no more likely to burn out than any other. The fact that any are burning out means simply that you are overdriving them.
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