Method for determining a compression characteristic, method for determining a knee point and method for adjusting a hearing aid

1. A method for determining a knee point of a frequency compression characteristic for a hearing device, which comprises the steps of:

determining a maximum audible frequency of a hearing device user;

determining the knee point by means of a predefined rule in dependence on the maximum audible frequency, parameters of the frequency compression characteristic constituted on a basis of frequency groups;

calculating the knee point using Bark scale values; and

calculating a coordinate f 13 cutoff of the knee point using the formula:

f _cutoff=1960·(( f _max_bark−no_bands_down+0.53)/(26.28−( f _max_bark−no_bands_down)),

where f_max_bark is the maximum audible frequency converted into a Bark value, and no_bands_down is a number of frequency groups defined in dependence on the maximum audible frequency.

2. The method according to claim 1 , wherein the knee point is in each case set above 1.5 kHz.

3. A method for determining a frequency compression characteristic, which comprises the steps of:

mapping an input value to an output value by determining a knee point of the frequency compression characteristic for a hearing device, the knee point being determined by the further steps of:

determining a maximum audible frequency of a hearing device user;

determining the knee point by means of a predefined rule in dependence on the maximum audible frequency, parameters of the frequency compression characteristic being constituted on a basis of frequency groups; and

wherein below the knee point each said input value is equal to a respective said output value;

calculating the input value f 13 source_max for the output value f 13 max, corresponding to the maximum audible frequency using a Bark scale, and the formula:

f _source —max= 1960·(( f _max_bark+no_bands_up)+0.53)/(26.28−( f _max_bark+no_bands_up)),

where f 13 max_bark is the maximum audible frequency (f 13 max) converted into a Bark value, and no_bands_up is a number of frequency groups defined as a function of the maximum audible frequency.

4. The method according to claim 3 , which further comprises setting a maximum compression rate to be 4.

5. A method for adjusting a binaural hearing system containing two hearing devices using the step of determining the frequency compression characteristic according to claim 3 .

6. The method according to claim 5 , wherein the frequency compression characteristic is determined for the hearing device user's ear having a lower hearing loss.