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Computational techniques available for linear chains are utilised in evaluating the density of states and amplitude correlations of certain types of multi-dimensional disordered harmonic systems. Computations are carriedout on such two-dimensional systemsconsisting of effectively up to 10' atoms, with relatively little computational effort. Certain systems among these are chosen as models of glasses, exhibiting the typical excess of low-lying states in the vibrational spectrum. The qualitative difference between one-and higher-dimensional systems follows from the fact that the Van Hove singularities of homogeneous systems are shifted from the edge towards the centre of the band. The singularity of a two-dimensional homogeneous system divides the spectral band into two domains where. respectively, the amplitude correlations exhibit a qualitatively different behaviour. These characteristics of the amplitude correlations persist to some extent also in the disordered-glass models.

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