An audio engineering basis of thumb is that individual electrodynamic drivers provide description performance over at most about 3 octaves. Multiple drivers (i.e., subwoofers, woofers, mid-range drivers, tweeters) are generally disposed in a complete loudspeaker scheme to provide performance beyond 3 octaves.

Full compass drivers often employ an additional cone called a whizzer: Visit Site a small, light cone attached to the joint between the exclamation coil and the primary cone. The whizzer cone extends the high frequency response of the driver and broadens its high frequency directivity, which would otherwise be greatly narrowed due to the outer diameter cone material failing to keep up with the central sound coil at higher frequencies.