Oleg is a personal fave of mine: his good taste and knowledge about paper cones and field-coils are a well kept secret... old world technologies... better, artisanal skills and workmanship.
Paper cones aren't really and only paper: it's a mix of rabbit-fur and other fibers, depending on wanted stiffness and size of the speakers.
I always fondly think about those Japanese paper masters when looking at Mr. Rullit's beauties... paper looks so organic and right in color and texture.
The sound of Oleg's creations is - reportedly from people I know who listened and owned the VERY best, cost-no-object - among THE VERY best on the planet.
Take your chance and browse this nice portfolio... I plan to meet him, soon and at last.