I want to record or capture voices from speaker or sound card on my computer win7, without microphone

Hi,
  It is possible to reacord audio which is sent to speaker. Using Windows Audio Session API (WASAPI) we can accomplish this. There is a mechanism called Loopback Recording. Using this technique we can capture the audio stream sent to speaker and record it. Below are the few link which could help you in resolving this,
http://msdn.microsoft.com/en-us/library/dd316551%28VS.85%29.aspx
http://mark-dot-net.blogspot.com/2008/06/what-up-with-wasapi.html
http://msdn.microsoft.com/en-us/library/dd370800%28VS.85%29.aspx
 
The below link has an sample application,
http://blogs.msdn.com/matthew_van_eerde/archive/2008/12/16/sample-wasapi-loopback-capture-record-what-you-hear.aspx
 
 
Regards,
raaj