A procedure is described for the selective removal of NMR signals assocd. with coupling consts. (J) exceeding a lower limit Jmin. The procedure is called \"low-pass J filtering\" since it leaves signals assocd. with small J couplings essentially unaffected. The procedure is explained for the suppression of neighbor peaks in heteronuclear relayed correlation spectra. The efficiency of the technique is demonstrated by using the relayed spectra of glucose in an equilibrated mixt. of a and b anomers. [on SciFinder (R)]