Interesting topic. I have made a lot of picture frames over the years where I have ebonized a variety of wood species including walnut, maple, mahogany, cherry, etc. I have used with good success the following procedure which is quite simple. Brush a generous coat of vinegar/steel wool mixture (which I always keep on hand) This turns any wood including maple a greyish brownish black and penetrates quite deep into the grain. This is followed by buffing the surface pretty vigorously with steel wool or woven grey polishing pad then apply Mohawk ultra-penetrating stain in black. (Behlen solar-lux is basically the same thing) The result is a deep clear black ebonized surface which does not obscure the grain of the wood. While I never seem to do the same thing twice when finishing picture frames, the basic process from here is to buff the surface again then apply BLO let that soak in and aggressively buff away the excess. Then apply thin coats of shellac and/or wax, and keep buffing and burnishing between coats. It sounds like a lot of work but it is not and it produces a very agreeable satin surface.
I will also suggest you experiment with these and other materials. If you make your vinegar mixture with rusty nails instead of steel wool it will produce a warmer brown grayish color, and ferrous sulfate produces a darker result, the effect of all of these iron concoctions can be modified by the concentration of the solutions. For wax on these frames I make my own brew of “George Frank water wax” which can be tinted with water soluble aniline dyes. Of course for black frames I make black wax.
My philosophy for finishing is; “It is never done wrong”, “It is just not done yet!” Keep rubbing till your surfaces look better than you hoped they would!
Good luck, Ken