If you want to adjust your microphone level in Windows 7, read this tutorial.
Steps to optimize Windows 7 for recording audio
1. Step Right click on speaker icon located in the task bar and select Recording devices.
2. Step In the opened sound window, select microphone and click Properties.
3. Step Click Levels tab.
4. Step Adjust the microphone level. I have made mine to 70. You can adjust as you desire..
4. Step Lastly, click OK
Optimizing recording audio is one of the important thing you may require to do as we usually use microphone for VOIP, skype, voice chat and more. You might want your friend / relative to hear your sound clearly.