A device including a processor and a memory is disclosed. The memory includes a noise spectral estimator to calculate noise spectral estimates from a sampled environmental noise, a speech spectral estimator to calculate speech spectral estimates from the input speech, a formant signal to noise ratio (SNR) estimator to calculate SNR estimates using the noise spectral estimates and speech spectral estimates within each formant detected in a speech spectrum. The memory also includes a formant boost estimator to calculate and apply a set of gain factors to each frequency component of the input speech such that the resulting SNR within each formant reaches a pre-selected target value.