Loads drawing current question

[TrojanHorse]

I’ve started to ponder a question that I thought I would ask this smart group. I think I now intuitively understand from all the work I’ve done on my security and home automation that loads draw electrical current so you can’t over supply a load with a power supply that provides a lot of amperage. This makes sense to me, in part because the power plant doesn’t shove all of its current through your outlet.
 
So then, why is it the case that you can blow out speakers by turning the volume up too high?
 
 
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[mwester]

Turning up the volume increases the voltage fed to the speakers -- and in accordance with Ohm's Law, as the voltage increases the current also increases, and the power delivered is equal to the voltage multiplied by the current -- so a small increase in voltage can have the effect of delivering a lot of power to the speaker.

In extreme cases, this can cause the voice-coil, which is made of very thin wire, to overheat and destroy itself -- in other cases, the increased power causes the diaphragm to move beyond it's designed limits, which can tear the paper/fabric, or physically damage the voice coil.

(You might have a follow-on question, which might be why the ISY isn't similarly damaged when fed with higher-voltage power supplies -- and the answer is that internally it has a voltage regulator, which serves to decrease the voltage to the designed level.  This part can safely handle up to the max supply voltage without damage... but not all devices have this; plugging your USB flash drive, for example, into a 12-volt power supply will cause it significant damage...)

[bgrubb1]

in addition when amps are turned up too high they tend to "clip" aka not produce a clean signal wave which has a high DC component for a signal not intended to be DC

 

[larryllix]

Power supplies are capable of higher currents. The may be rated as such but they cannot produce current.  It is up to the load (speaker) to draw that current. Loads will typically draw higher currents when a higher voltage is put to them.

So the voltage coming out of your amp is like the pressure in your garden hose. The current is like the flow of water coming out of your hose nozzle. If the nozzle (speaker) doesn't allow the water to come out no amount of pressure (voltage) will make it flow. It takes two to tango.

I addition to the above effects if your speaker cone ever slams against the magnet (bottoms out) you will likely drop to the floor, wondering if somebody is shooting a gun in your house.

 

[Teken]

I’ve started to ponder a question that I thought I would ask this smart group. I think I now intuitively understand from all the work I’ve done on my security and home automation that loads draw electrical current so you can’t over supply a load with a power supply that provides a lot of amperage. This makes sense to me, in part because the power plant doesn’t shove all of its current through your outlet.
 
So then, why is it the case that you can blow out speakers by turning the volume up too high?
 
 
Sent from my iPhone using Tapatalk

To be clear you can turn the volume to its maximum limit without issue. It comes down to the speaker having the same or higher power handling of the output of the amplifier.

Next, you can also have the volume at maximum and nothing will happen so long as the input signal is off or set below a threshold that would cause damage.

This is done all the time in professional environments to insure no matter what a stupid fool can’t blow out the speaker system.

[TrojanHorse]

Thanks everyone for the thoughtful responses.  I now have a better understanding of one more thing in this world thanks to you guys!!