SPECTRAL_CLEAN MULTI

        [BUNDLES\]SPECTRAL_CLEAN MULTI  Ns1 [Ns2 ...]

    Clean a (spectrally) smoothed version of the data cube, then start from this
    result to continue Cleaning with the original spectral resolution.

    To  be  implemented:  the method can be generalized to more than 1 smoothing
    scale, by performing the smoothing in descending order (Ns1 > Ns2  >  ...  >
    1).  This may allow to catch signals that have widely different widths.