I just tried the other 2 sets of tips and for my ears, the default double flange fit and sounded the best by far. The large made the bass very boomy, not tight and controlled at all. The small had no bass and highs were shrill. Doing some more critical listening, I've determined the greatest weakness of these earphones - the soundstage. Soundstage never got better with burn in. The music never extended beyond the width of my head. From the goldenears graphs, the Quads measure VERY well, and I can hear this, but they can't measure soundstage, and this is what I've determined makes the Quads inferior to the great earphones.