A method for enhancing speech output by an electro-acoustical transducer in a noisy listening environment, comprising: filtering an input audio signal x( t) using an adaptable filter H(z) to produce a filtered audio signal x ( t), wherein x ( t) = H(z)x( t); providing to the electro-acoustical transducer an analog signal corresponding to the filtered audio signal to produce a sound wave corresponding to the filtered audio signal; and prior to filtering the audio signal using the filter, configuring the filter such that, with respect to one or more frequencies, the filtered audio signal has a higher signal level than the input audio signal, and such that the overall signal level of the filtered audio signal ( sl f) is substantially related to the overall signal level of the input signal ( sl r) such that sl f = sl r × c, where c is a constant, wherein the step of configuring the filter comprises: estimating, based on at least a portion of the input audio signal, a signal spectrum P x ( f); and estimating, based on at least a portion of an audio signal corresponding to a signal received by a an acoustic-electronic transducer, a noise spectrum P y ( f) and for each of a plurality of frequencies f, determining a gain function γ ( f) for the filter based, at least in part, on the estimated spectra P x ( f) and P y ( f), wherein the step of determining γ( f) comprises: for each of the plurality of said frequency f, determining SNR( f), where SNR( f) is a function of P x ( f) and P y ( f) and determining γ ER ( f), wherein, for f < f t, γ ER ( f) = min(1,max(c1, SNR( f)/c2)), wherein f t, c1 and c2 are predetermined values. filtering an input audio signal x( t) using an adaptable filter H(z) to produce a filtered audio signal x ( t), wherein x ( t) = H(z)x( t); providing to the electro-acoustical transducer an analog signal corresponding to the filtered audio signal to produce a sound wave corresponding to the filtered audio signal; and prior to filtering the audio signal using the filter, configuring the filter such that, with respect to one or more frequencies, the filtered audio signal has a higher signal level than the input audio signal, and such that the overall signal level of the filtered audio signal ( sl f) is substantially related to the overall signal level of the input signal ( sl r) such that sl f = sl r × c, where c is a constant, wherein the step of configuring the filter comprises: estimating, based on at least a portion of the input audio signal, a signal spectrum P x ( f); and estimating, based on at least a portion of an audio signal corresponding to a signal received by a an acoustic-electronic transducer, a noise spectrum P y ( f) and for each of a plurality of frequencies f, determining a gain function γ ( f) for the filter based, at least in part, on the estimated spectra P x ( f) and P y ( f), wherein the step of determining γ( f) comprises: for each of the plurality of said frequency f, determining SNR( f), where SNR( f) is a function of P x ( f) and P y ( f) and determining γ ER ( f), wherein, for f < f t, γ ER ( f) = min(1,max(c1, SNR( f)/c2)), wherein f t, c1 and c2 are predetermined values. estimating, based on at least a portion of the input audio signal, a signal spectrum P x ( f); and estimating, based on at least a portion of an audio signal corresponding to a signal received by a an acoustic-electronic transducer, a noise spectrum P y ( f) and for each of a plurality of frequencies f, determining a gain function γ ( f) for the filter based, at least in part, on the estimated spectra P x ( f) and P y ( f), wherein the step of determining γ( f) comprises: for each of the plurality of said frequency f, determining SNR( f), where SNR( f) is a function of P x ( f) and P y ( f) and determining γ ER ( f), wherein, for f < f t, γ ER ( f) = min(1,max(c1, SNR( f)/c2)), wherein f t, c1 and c2 are predetermined values. for each of the plurality of said frequency f, determining SNR( f), where SNR( f) is a function of P x ( f) and P y ( f) and determining γ ER ( f), wherein, for f < f t, γ ER ( f) = min(1,max(c1, SNR( f)/c2)), wherein f t, c1 and c2 are predetermined values.