A fitting system is described for fitting electrode contacts of cochlear implant electrode array implanted in a cochlea of an implanted patient. A test stimulation generator delivers to at least one of the electrode contacts a test stimulation sequence at a variable charge level and a variable stimulation rate over time, wherein the charge level and stimulation rate are inversely related as a function of a defined loudness percept by the implanted patient to the test stimulation sequence. A response measurement module obtains objective response measurements of auditory neural tissues of the implanted patient that are affected by the test stimulation sequence. A fit mapping module defines a patient-specific fit map for the electrode contacts of cochlear implant electrode array based on the objective response measurements.