My personal list of Cone Materials, best sounding first. Notice the relationship of hardness to sound quality.
Diamond
DH (Diamond Hardness) (ceramic) Cones
Tempered High Carbon Steel
Steel
Brass
Aluminum
Carbon Fiber
Rubber type materials
Diamond
DH (Diamond Hardness) (ceramic) Cones
Tempered High Carbon Steel
Steel
Brass
Aluminum
Carbon Fiber
Rubber type materials