Early this spring , growing on a public building in the city, I saw a FABULOUS white clematis that was unbelievably fragrant. Would that have been Clematis Armandii ? It was huge !
C. armandii has long pointed leaves, different from most Clematis.
Probably :-) Not too many early blooming, highly fragrant big vine types.....armandii fits the bill. If it were in bloom a bit later - like now - I'd suggest the possibility of C. montata 'Wilsonii'. Also a big, white flowered, fragrant clem.