Finally I managed to get it right!
Profiled again my recto! this time via my Behringer DI or my THD hotplate, results are impressive! My recto sounds basically the same via kemper and my ritter poweramp !
What I did wrong before was using the hotplate as a load box! if you do this the amp won't react the same as plugged directly to a cab!
Profiling through the Behring or through the THD didn't get me different results, they both sounds the same!
Guys if you wanna play live with your real recto/5150/marshall tone! give it a try it's really impressive