Thanks for all of the info!
Just an update, I made a 4.7k mod Y cable for my AT853's and must say that the results are fantastic! I also used my hacked CK93's on the Y cable and also fantastic results! Was skeptical about there not being enough plug in power for the AKGs but that was not the case! Highly suggest either the AT or AKGs with the 4.7k mod into the M10!
Will have a CF mod Iriver up for sale shortly!