Method and apparatus for controlling band split compressors in a hearing aid

A hearing aid, comprising:

• an input transducer which is configured to transform an acoustic input sound signal into an electric input sound signal;
• a band split filter unit which is configured to filter the electric input sound signal into a number of frequency bands thereby obtaining a set of band split signals;
• a signal level estimation unit which is configured to determine a signal level for each of the band split signals;
• a grouping control unit which is configured to allocate the frequency bands into at least two groups, wherein at least one group comprises signal levels of at least two frequency bands, and to calculate a compressor input parameter for each band split compressor, wherein the compressor input parameter for at respective band split compressor is calculated based on the signal levels of the frequency bands of the group associated with said respective band split compressor;
• a band split compressor for each frequency band which is configured to determine a compressor gain based on the respective compressor input parameter, and to amplify each of the band split signals according to the compressor gain determined by the respective band split compressor;
• a summing unit which is configured to sum the amplified band split signals to an electric output signal;
• and
• an output transducer which is configured to transform the electric output signal into an acoustic output signal.