The intelligibility of speech in noise can be improved by modifying the speech. But with object-based audio, there
is the possibility of altering the background sound while leaving the speech unaltered. This may prove a less intrusive approach, affording good speech intelligibility without overly compromising the perceived sound quality. In this
study, the technique of spectral weighting was applied to the background. The frequency-dependent weightings for adaptation were learnt by maximising a weighted combination of two perceptual objective metrics for speech intelligibility and
audio quality. The balance between the two objective metrics was determined by the perceptual relationship between
intelligibility and quality. A neural network was trained to provide a fast solution for real-time processing. Tested in a
variety of background sounds and speech-to-background ratios (SBRs), the proposed method led to a large intelligibility
gain over the unprocessed baseline. Compared to an approach using constant weightings, the proposed method was able to
dynamically preserve the overall audio quality better with respect to SBR changes.