hi im trying to put my cdlc songs from my rocksmith 2014 on to my old rocksmith is there a way to change the psarc flie to a dat file with the toolkit ?

There is no automated way to do this (that I know of), but it can be done manually with toolkit and EOF if you are up to the challenge. Unpack RS2014 CDLC with toolkit.  Open xml(s) and audio in EOF.  Save as RS1 format from EOF.   Use toolkit to create a new RS1 CDLC package from the EOF RS1 files.. 

 

Obviously there is more work to do than these few pseudo instructions.

And i'm not sure why would you ever want to do that since the first RS offers way less capabilities when it comes to tuning, recognition and technique (gosh those bends...).

 

Unless you only own the first game? But then you'll bet better off buying the other one during the coming steam sale for something like -50% of the actual price and it would be really worth it.