.Motor structure - Innovation

. Konstant Bl(X)

Get a constant force factor over the full cone excursion is a key point to keep very low distortion.

The best solution is the under-hung voice coil, which means the voice coil is shorter than pole pieces.

This solution is very seldom been used because the magnetic field in the gap is much lower than the conventional overhung solution… and use a bigger magnet make it expensive.


Thanks to our dual magnets design, and the optimized shape of the pole pieces, we provide constant force factor over the full nominal excursion, and we avoid low magnetic field value.

Crédit photo: .Kartesian company

. Kiet air flow

Manage the air flow in the speaker is important to cool down the voice coil, and avoid any inner resonator. Nevertheless, for the speakers with high cone excursion, keep the air flow quiet in any situation is challenging; noises happen in the air flow with air speed variation.


We have developed special items, strategically located to manage the air flow and keep its speed constant. As a result, our speakers keep quiet working, without any air flow noise, even during the highest cone excursion.

Crédit photo: .Kartesian company

. Konstant Le(X)

Inductance variation according to the frequency and the cone excursion creates distortion. The engineering target is to keep the inductance constant on both criteria. Furthermore, the inductance variation creates unstable loading for the amplifier and requires important current capabilities.

Thanks to our .Konstant Le(X) devices, based on Aluminum and cooper rings, strategically positioned, the inductance is linear in any circumstances.

Crédit photo: .Kartesian company

. foKus field

Magnetic field is a topic more complicated than using oversized magnet, or exotic vintage grade. Provide intense magnetic field to the voice coil doesn't means nothing, and can lead up to up-cost without any performance improvement.

For each of our speaker, we develop the motor structure with accurate dynamic simulation, and prove it out their relevance through measurements.

Crédit photo: .Kartesian company

. Kooling

Cool down the voice coil is necessary for high power handling speakers, such as professional application. Well known solution (high temperature material for the former, bigger wire section, ...) limit the performances because it increases the weight of the moving mass.

We have developed different approach using specific speaker parts as cooling radiator. We don't fight to support more power, we transfer it to the environment.

Crédit photo: .Kartesian company