Can the 1990-issue Lionel 700E sound system be upgraded?

I just bought a 1990 Lionel 700E Hudson and love the physical details, but its original Railsounds-1 system leaves a lot to be desired compaired to today’s modern marvels. Can this 700E’s soundsystem be upgraded, perhaps also to included TMCC-1 or TMCC Legacy? I’ve looked on Lionel URL and other on-line places, but can’t find any references. My closest Lionel dealer (who quite frankly is pretty limited) says no, but others in my train hobby community say it can easily be done.
Thanks!

Its possible to upgrade about anything depending on how much you want to do. Electric Railroad Company offers upgrade kits for TMCC control and sound as well as does Digital Dynamics.

If you want to upgrade, and don’t want to do it, I offer upgrade services.