|If you are using Windos 7 then follow these steps to turn off one speaker. It is very well possible (It is called balancing)|
Go to Start menu>Control Panel>Hardware and sound>Sound
Another window will open
Now go to speaker properties and select the Levels tab and from there you can balance your speakers.
Chose the audio output and click balance and then drag the speaker bar you want to turn off to the end (0).
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