In case you want to place a loudspeaker close to a CRT, magnetically shielded drivers are mandatory. Reducing the impact of the magnetic field at a later stage is possible by employing compensation magnet or shielding caps.
The following compensation magnets should be attached to the rear of the driver causing the two magnets to draw apart (as long as they don't touch).
KM 80 particularly suitable for Visaton AL 130, AL 170, DSM 25 FFL, DTW 8.12 NG, G25 FFL
KM 140 particularly suitable for Visaton AL 200, AL GF 200, GF 250, TIW 250, TIW 360, TIW 400, W250S, W300S, WSP 21S