The C168-6-990 is a 7 inch midrange driver with ceramic dome, being the first in an entirely new approach to Accuton speaker design. We pushed on speaker evolution again by inventing the 4D (Direct Dome Drive Design) concept, providing the shortest distance between voice-coil winding and dome. The spider is not connected to the voice-coil former anymore, thus removing 15mm of unneccessary former length. The result is an extremely true reaction of the dome. The low loss rubber surround is connected to the voice-coil former,preventing any kind of interaction with the dome. An open fabric spider centers the dome with a direct connection and high linearity. An ideal acoustical center has been achieved, which is identical with our tweeters. Its novel designed underhung motor does not cover the back-side of the dome, eliminating the chance for reflections and energy storage.
Main Features:
Ideal acoustic center
Proprietary 4D concept
No rear reflections
Underhung motor
In 0.2 cubic foot (6 liters) with 20% filling, your f3 is 250Hz and f6 is 150Hz. Impedance peak would be around 100Hz in this box.