Hearing impaired persons lose their ability to discriminate speech in ambient noise. Actual Hearing Aids (H.A.), us us ally amplify equally speech and noise, thus they do not provide any speech enhancement. Two techniques are proposed to be used on HA, based on real time adaptive beamforming to reduce the ambient noise thus enhancing the main speech signal. These techniques are evaluated in real time using a specially developed board plugged in a Personal Computer. This evaluation concerns the directivity patterns, the signal to noise ratio and intelligibility improvement in realistic noisy situations. The results are presented.