AIR core coils
The optimal core material for coils is air. For physical reasons, air coils, with respect to pulse fidelity and freedom from distortion, are always superior to all metal core coils. They can be used in all areas; both as a high pass in the midrange, as a bass coil (with high conductor cross section) as well as correction elements (with a thinner wire cross section).
Fine drawing, precision, dynamics and distinguish coils with air core in front of all others. In high-quality speakers, they therefore form the basis for realistic, harmonious-beautiful music enjoyment.