A system comprising: a spectral analysis facility configured to determine a frequency spectrum of an audio signal presented to a cochlear implant patient, the frequency spectrum comprising a plurality of frequency bins that each contain spectral energy, and generate a modified spectral envelope of the frequency spectrum of the audio signal; and a pitch enhancement facility communicatively coupled to the spectral analysis facility; characterised in that said pitch enhancement facility is configured to identify at least one frequency bin included in the plurality of frequency bins that contains spectral energy above the modified spectral envelope in said bin and each frequency bin included in the plurality of frequency bins that contains spectral energy below the modified spectral envelope in said corresponding bin, enhance the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope by applying a positive gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope, and compress the spectral energy contained in each frequency bin identified as containing spectral energy below the modified spectral envelope by applying a negative gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy below the modified spectral envelope. a spectral analysis facility configured to determine a frequency spectrum of an audio signal presented to a cochlear implant patient, the frequency spectrum comprising a plurality of frequency bins that each contain spectral energy, and generate a modified spectral envelope of the frequency spectrum of the audio signal; and determine a frequency spectrum of an audio signal presented to a cochlear implant patient, the frequency spectrum comprising a plurality of frequency bins that each contain spectral energy, and generate a modified spectral envelope of the frequency spectrum of the audio signal; and a pitch enhancement facility communicatively coupled to the spectral analysis facility; characterised in that said pitch enhancement facility is configured to identify at least one frequency bin included in the plurality of frequency bins that contains spectral energy above the modified spectral envelope in said bin and each frequency bin included in the plurality of frequency bins that contains spectral energy below the modified spectral envelope in said corresponding bin, enhance the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope by applying a positive gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope, and compress the spectral energy contained in each frequency bin identified as containing spectral energy below the modified spectral envelope by applying a negative gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy below the modified spectral envelope. identify at least one frequency bin included in the plurality of frequency bins that contains spectral energy above the modified spectral envelope in said bin and each frequency bin included in the plurality of frequency bins that contains spectral energy below the modified spectral envelope in said corresponding bin, enhance the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope by applying a positive gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy above the modified spectral envelope, and compress the spectral energy contained in each frequency bin identified as containing spectral energy below the modified spectral envelope by applying a negative gain to the spectral energy contained in the at least one frequency bin identified as containing spectral energy below the modified spectral envelope.