Having a good hall is fundamental to the development of a coherent sound. and basically a personality. This is what has happened over decades in places like Vienna or Amsterdam to name the most obvious examples. This is why I am fearful for the OP.
As I explained in a 2006 blog entry on an Overgrown path, French orchestras have been shifted from one inadequate hall to the other. The newly renovated Salle Pleyel is a genuine success and the resident orchestras, Chung's Nouvel Orchestre Philharmonique de Radio-France and the OP have made strong progress achieved by regular work in a hall where they can hear themselves.
Perspectives at the OP should be bright, Paavo Järvi, their new chief conductor, is a glorious musician and the future season looks superb. Why then do this forthcoming move to a new hall ? I have the following concerns:
- Past experience with the Bastille is a proof that big state-funded construction plans can really go bad ...
- Is there really an audience for a new concert hall: Paris has Bastille, Garnier, (Chatelet is definitely a hall for musicals and no longer for classical music), the Théâtre des Champs-Elysées, Salle Gaveau, la Cité de la musique, ... and many other which I have forgotten ?
- finally, the new hall would be at periphery of Paris, accessing it is not simple and it is not the most pleasant of the Parisian neighbourhood. Is not there a risk of alienating many ?