With song being the sole basis for selection, the appearance of the Roller has altered little over the years from that of the original, but for commercial purposes, clear yellow, orange or white Rollers are now available.The British song standard recognizes thirteen well-defined song passages called "rolls" and "tours", each of which constitute a distinct melodic entiry, although few, if any, birds are capable of uttering all of them.
The chief sounds being produced: "Hollow Roll", "Bass Roll", "Bell Roll", "Water Roll", "Glucke", "Water Glucke", "Glucke Roll", "Flutes", "Shockel", "Hollow Bell", "Deep Bubbling Water".
