Download Estimating the amplitude of the cubic difference tone using a third order adaptive Volterra Filter Design method of a nonlinear filter to estimate the amplitudes of cubic difference tones is presented. To this end, a third-order Volterra filter is used to model the nonlinearity of our auditory system, and the filter coefficients are obtained using an adaptive process. The results show the filtered outputs follow very closely the experimental data as the intensity levels and the frequencies of inputs vary especially when the frequency separation between the two primary tones is not large.
Download Accurate Plate Reverb Parameter Estimation Using Two-Stage Evolutionary Search We describe our submission to Task A of the 1st DAFx parameter estimation challenge. The task is to recover the six physical parameters of a simulated metal-plate reverberator—its dimensions and material properties—from a single impulse response (IR). We treat this as a black-box optimization: candidate parameter sets are fed to the simulator and scored by a loss against the target IR. The method has two stages. The first uses CMA-ES, an evolutionary optimizer, to recover five of the six parameters, comparing IRs under an amplitude-normalized loss. Amplitude normalization makes the search robust but discards the cue to the sixth parameter, the plate’s surface density; a second stage therefore estimates it alone, with a ternary search on the un-normalized loss. As the choice of loss strongly affects the search, we select it beforehand, and analyze why compression in the common multi-scale spectral loss degrades recovery. Finally, we test our method on a validation set of 50 IRs, discuss a pathological failure mode, and ablate to justify having two different stages instead of a unified CMA-ES search.