You can enjoy karaoke at home without a karaoke machine, by attaching a microphone to your computer and playing the output through external speakers. Windows 8 enables line-in ports automatically, but if you can't hear your singing over the backing track you may need to configure your sound settings. If you have a condenser microphone, connect it to the computer through a pre-amplifier and make sure the mic is plugged into an AC socket.
Connect your microphone to the computer through the line-in port. Use the same port if you are connecting the microphone through a pre-amplifier.
Open the Settings charm and type "Sound" into the Search box. Click "Sound" and choose the "Recording" tab.
Check that your microphone is shown as the default device. If it doesn't appear in the list, right-click in an empty area of the Sound window and check "Show disabled devices" and "Show disconnected devices." Right-click on your microphone and choose "Enable."Select the microphone you want to use, choose "Set default" and click "Properties."
Click the "Levels" tab. If the Muted button appears next to the microphone, click the button to un-mute it.
Click and drag the slider bar to increase the volume to at least 75. If other line-in devices such as a microphone boost are available, increase the volume on those as well. Click "OK."