receiving an input audio signal at a client device;

determining an audio spectrum of an audio signal frame of the input audio signal;

determining a respective energy value for each frequency band of a plurality of frequency bands in the audio signal frame;

determining, for each frequency band of the plurality of frequency bands, a difference between the respective energy value of the respective frequency band and a predetermined ideal band value associated with the respective frequency band, wherein the respective energy value is a ratio of energy within a given band to an entire energy of the plurality of frequency bands; and

selectively applying, in real time, based on the differences, per-band equalization to the input audio signal to adjust the respective energy value for each frequency band of the plurality of frequency bands to produce an output audio signal.