Variac on fully restored MC-30's


Should I use a variac on fully restored MC30's who were not powered for a while?
I just had them delivered. They are Yves Beauvais restored from around 3 years ago but I'm not sure when was the last time they were powered.

By the way, does anyone know how come Yves website is down?
yyman23
You could just use a dim bulb tester.