“…Most of the formant frequencies are still present in the AMR condition, however, with a missing LB, a spectral imbalance towards high frequencies results, which consequently affects female speakers stronger than male speakers. Of course, UB-ABE improves speech quality [28], [33], however, it does not sufficiently restore spectral balance over sounds, especially for female speakers. In [12] it was already stated, that only the simultaneous extension towards high and low frequencies leads to the maximum improvement possible, rather than the exclusive use of only one of the techniques.…”