I thought you might like to know that when I lived in USA I bought a KN7000 and it was brought back with my other items when I returned to UK. I have been successfully using it with a step down transformer for 2 years. When I went out to USA I took a KN1600 (UK model) and had that stepped up to UK voltage for 3 years so the transformer is the way to go and there have been no problems. These transformers are available at Maplin in UK but I do not know where to get them in France.
Genos, V-Console, Korg Pa2x, Technics KN7000, Roland. BK-7M Module, Korg Micro Arranger.