ORIGINAL: bubbagates
Another thing is the bigger the diameter of the 3-blade prop the less efficency is lost which means there is more time for the air to "recover" (meaning less turbulent air) between the blades
HUH? Assuming no difference in RPM and both are 3-blade, the TIME (or frequency) between blades remains unchanged.
In addition, the blade tips of the larger props will be traveling faster than the smaller prop which will cause more noise.