Not unless the new preamp adds features you may want like network streaming, HD audio, or a subwoofer output and bass managment.
Dont get caught up in how products "sound". Well designed products, such as those you own, sound like nothing. They are supposed to be transparent to the source material.
Source material and loudspeaker placement/listener position/room setup/reflections/frequency response/T60 among others determine the listener experience.
The only pieces of gear I know of that account for all of these are products with Dirac. Since you are running a PC, you can try Dirac for free and see how you like it if you want.
