Configurable hearing aid comprising a beamformer filtering unit and a gain unit

A hearing aid comprising

• a forward path comprising
• a multitude of input units for providing a multitude of electric input signals INi, i=1, . . . , M, representative of sound,
• a multi input beam former filtering unit for providing a beam formed signal YBF from said multitude of electric input signals,
• a gain unit for applying a hearing aid gain GHA to said beam formed signal YBF, and providing a processed signal, and
• an output unit for providing stimuli perceivable by a user as sound based on said processed signal or a signal derived therefrom,
• the hearing aid further comprising
• a gain control unit for limiting said hearing aid gain GHA, to a modified full-on gain value G′FOG, wherein
• the multi input beam former filtering unit is configured to apply a current frequency dependent directional gain GDIR,i to each of said multitude of electric input signals INi, and wherein the gain control unit is configured to determine the modified full-on gain value G′FOG in dependence of said current directional gains GDIR,i, i=1, . . . , M, and a previously determined full-on gain value GFOG, and
• the gain control unit is configured to control the beam former filtering unit in dependence of the current full on gain margin ΔGFOGm, ΔGFOGm being a difference between the previously determined full-on gain value GFOG and the sum of the current hearing aid gain GHA and the maximum value GDIR,max of the current directional gains.

A method of operating a hearing aid comprising

• a forward path comprising
• a multitude of input units for providing a multitude of electric input signals INi, i=1, . . . , M, representative of sound,
• an output unit for providing stimuli perceivable by a user as sound based on a processed signal or a signal derived therefrom,
• the method comprising
• providing a beam formed signal YBF from said multitude of electric input signals,
• applying a current frequency dependent directional gain GDIR,i to each of said multitude of electric input signals INi,
• applying a hearing aid gain GHA to said beam formed signal YBF, and providing a processed signal, and
• providing a previously determined full-on gain value GFOG,
• limiting said hearing aid gain GHA to a modified full-on gain value G′FOG,
• determining said modified full-on gain value G′FOG in dependence of said current directional gains GDIR,i, i=1, . . . , M, and said previously determined full-on gain value GFOG,
• determining a smoothed value <GDIR,max> of the maximum value GDIR,max of the current directional gains, and using the smoothed value <GDIR,max> in the determination of the modified full-on gain value G′FOG, e.g. G′FOG=GFOG−<GDIR,max>, and
• controlling a release time and/or an attack time of the smoothing in dependence of a current full on gain margin ΔGFOGm, ΔGFOGm being a difference between the previously determined full-on gain value GFOG and the sum of the current hearing aid gain GHA and the maximum value GDIR,max of the current directional gains ΔGFOGm=GFOG−(GHA+GDIR,max).