A method for adjusting parameters of a hearing prosthesis system includes adjusting a control to shift an audiogram associated with a first stimulator, applying a prescription rule using the shifted audiogram to adjust a cross-over frequency that defines a first frequency range and a second frequency range. The first stimulator is configured to apply stimulation signals in the first frequency range and a second stimulator is configured to apply stimulation signals in the second frequency range. The method also includes applying the prescription rule using the shifted audiogram to determine gain and maximum power output (MPO) levels for the first frequency range associated with the first stimulator.