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Can I plug a pair of 240v computer speakers into 110v wall outlet?

Plugging in the reverse (110v speaker in to 220v wall outlet) I assume would destroy the device in question but if I provide lower voltage than necessary, would it be damaged? Would it be usable?

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Shouldn't this question go here ? – VenkatH Dec 3 '12 at 6:12
@VenkatH They don't deal with consumer electronics - not sure if they would accept this. – Bob Dec 3 '12 at 7:32
up vote 1 down vote accepted

Yes you can. Remember that the voltage is alternating. 240V is actually ~240V. When the UK downgraded from ~240V to ~230V there was a lot of nonsense talked about certain appliances 'running slower', but we happily used the same devices.

A lot of electronic stuff is dual voltage -- and marked as such -- and just works of course. I found that nearly all of my UK-bought computer related stuff just worked in the US once plugged in with an appropriate adaptor.

A surprising amount of electronic kit which is marked as 240V only also works fine at 110V with no transformer needed. Examples are various radios, a small hifi and a pair of powered computer speakers. There doesn't seem to be any danger in trying this going in the 240V - 110V direction, doing it the other way around wouldn't be a good idea of course.

Ordinary incandescent light bulbs work but are around half as bright as normal. One surprise is that all the low energy light bulbs I've tried have worked fine -- I guess a lot are probably dual voltage and just not marked as such.

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If it's not dual-voltage, this can be very dangerous. If the supply is semi-smart, at the lower voltage, it will draw much more current than intended. – David Schwartz Dec 3 '12 at 7:41
There is the potential for damage. Lower voltages mean a higher current is required for the same power. A higher current means more heat, especially if the wiring is too thin (power loss as heat is equal to resistance multiplied by current squared). More heat means things melting/catching fire - this is especially obvious with motors. – Bob Dec 3 '12 at 8:37
@Bob Doesn't seem like speakers would draw enough power to get that hot though. – Jack Dec 4 '12 at 9:22
@Jack They shouldn't. I agree with not going crazy with electric motors, etc. Speakers however, are not going to suffer from lower voltage throughput. – Ian Atkin Dec 4 '12 at 9:26

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