We present an efficient implementation of the Amplitude Spectrum Capon (ASC) estimator. The implementation is based on the FFT and an efficient computation of the Cholesky-factor for the inverse covariance matrix. The Cholesky-factor is obtained from the linear prediction coefficients as computed by the modified covariance method. The implementation is significantly simpler than previous implementations, and it will yield spectral estimates of a similar quality as these. A short discussion on the differences between different Capon estimators is also included.