Nothing, it will not operate properly.

You will burn it out promptly. Did you do it? Get a step down transformer.

It will fry the voice coil with either, speakers don't get voltage applied directly to them, actuall they do get voltage, but not that high.
Are you trying to listen to Electricity?
You need an Amp or something.
Is this a wireless speaker.
How did you do this, are your 120 and 240 volt recepticles the same configuration, or did you change the plug end, trying to figure out?

I did this by accident. I live in Korea now and forgot that it was 220.
It will not work now.
Can I get this fixed?

I did this by accident. I live in Korea now and forgot that it was 220.
It will not work now.
Can I get this fixed?

I did this by accident. I live in Korea now and forgot that it was 220.
It will not work now.
Can I get this fixed?

Are these powered speakers or a power supply? Does a 120V plug look like a 240V outlet in Korea?

Duh, sorry I took it the other way around. Yea a 120 volt device powered by 220 volts will destroy it.

OMG! And I had the greatest of confidence in you! Too much voltage to the gray matter! Happens to me all the time!LOL, Brian

Either age, or the mind altering substances.

Definitely the age.And trying answers questions at 5:50 in the morning before work.

After realizing their is probably more to this, If Powered Speakers, A Tech will apply the correct Voltage follow into the enclosure, check for power in and out of any fuse(may be all that is wrong, then in and out of Transformer, and so on, you could get lucky.