ENGL Savage

it's basically the same sound when I use my cab.

Well... do some tweaking to have the sound that suits you coming out of the cab (what cab do you use), and then use those settings for the FX-out takes.

when i listen to the last sample you've made it sounds like there's too much presence, which explains this fizzy top-end (i had the same problem when i miked my engl stack the first time)

try lowering the presence first.

then if it still need some improvement maybe a tad less bass/gain
 
Presence doesn't work with impulses because it affects only the power section.

Anyway, Noumenon, Savage is not a plug and play amp like the 5150..when I bought mine I try different settings for some weeks before find a decent sound..also the 2 gain pots make the work more difficult.
Try to see which preamp tubes brand you have