This is the blurb from Morels website:
QUOTE
The Supremo 2-way system offers car audio enthusiasts a combination of state-of-the-art technological savvy and superior sound reproduction. Designed to confront the unique challenges of car audio, the Supremo woofers deliver unsurpassed performance – representing the pinnacle of Morel's component line.
Supremo is based on Morel's linear dynamic under-hung voice coil configuration, which allows the voice coil to move in a significantly higher magnetic field and remain there during operation. This configuration enables linear excursion of the coil and higher magnetic flux, eliminating inter-modulation distortion while considerably improving the dynamic range, transient response and efficiency.
Supremo SW woofers employ an aerodynamic die-cast Uniflow chassis to minimize sound reflection distortion and provide shallow mounting capabilities. The 3" EVC Hexatech voice coil, coupled with its unique Hybrid magnet motor structure (combined ferrite and neodymium magnets) produces remarkably high power capabilities, high efficiency, as well as a wide and natural dynamic range. Supremo SW woofers are available in 5", 6" and 9".
Morel's unique C.A.R filter (Controlled Acoustic Resistance) enables the Supremo SW woofers to perform well in "free-air", or infinite baffle environments, thus providing acoustical accuracy and greater cone movement control.
The Supremo 2-way component system has been engineered as an active speaker system that maximizes the full potential of its drivers and enables installers to employ various frequency cut-off points and slopes.