I'd like to make a shelf for my turntable that attaches to the wall in my music room as the floor in that particular room is a bit springy (sadly). I'm wondering if anyone has any suggestions what would be a good material for this purpose. Any suggestions for bracket type would be welcome as well.

Steel, square tubing, mdf shelf. Put the shelf on points. Drive the mounting screws for the shelf into wall studs.

Hi :), Big heavy braces - all stud fastened with substantial screws or lag bolts, no floor contact if the springy-ness extends to the area of the wall/floor joint? Steel OK for braces, but you can built it all out of wood if you want to. What table (sprung base or mass dampened?). Granite slab or MDF with glued on veneer? The deader the better :)