Step 1:

Go to http://audacity.sourceforge.net/ to download and install Audacity.

 

Step 2:

Run Rocksmith 2014 and make sure Audio Exclusivity is turned off in the Options menu, then quit.

 

Step 3:

Open up the Recording Devices tab of the Sound Control Panel (Easily done by right clicking on the speaker icon in the system tray and selecting Recording Devices.

 

Step 4:

Right click inside the Recording Devices list and ask it to Show Disabled Devices

 

Step 5:

Find the Stereo Mix disabled device and enable it.

 

Step 6:

Run Audacity, and select Stereo Mix as your recording input

 

Here's a little GIF I made to illustrate steps 4, 5 and 6

 

http://img842.imageshack.us/img842/2018/rra.gif

 

Step 7:

Run Rocksmith 2014 once again, and get ready to play whatever it is you want to record, ie, a song, or session mode, or whatever.

 

Step 8:

Just before you hit the button to begin playing the song or start playing the session, ALT-TAB back out to Audacity and hit the Record button, then ALT-TAB back into Rocksmith 2014.

 

Step 9:

Play

 

Step 10:

When you've finished, ALT-TAB out to Audacity again and stop the recording.

 

Step 11:

In Audacity, hit Play to listen to what you just recorded.

 

source

What when I do not have Stereo Mix? Look at mine's tab:

 http://snag.gy/8vqd0.jpg

 

(showing both disabled and disconnected deviced)

pouvez-vous me dire ce que vous système est win7 xp ou win8

 

aussi avez-vous pensé à mettre les pilotes de votre journée de la carte son?

 

I suggest you also install asio4all on your Machine

https://www.google.fr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CEEQFjAA&url=http%3A%2F%2Fwww.asio4all.com%2F&ei=nr0QU6nCD8bnywPSqIGgAQ&usg=AFQjCNGjP4O47gXORY41xuMS2_YnsGsoRw&sig2=8YtVPK5GapoGdY7WObQL_Q&bvm=bv.61965928,d.bGQ