Through this paper the results of applying three different Adaptive Noise Cancelling Algorithms for Speech Enhancement in Robust Speech Recognition Command-Driven Interfaces are presented and discussed. Time-domain methods related with Recursive Least Squares Lattice-Ladder Filters with a posteriori updating show the best cancelling behaviour, although at a higher computational cost. The influence of microphonic separation is also evaluated. The best results are obtained for cardioid microphones with a separation of around 20 cm. taking advantage of their angular properties to prevent speech crosstalk in the reference microphone, thus reducing the computational cost required to acceptable limits.