Abstract: A method of separating signal classes in a stored signal quantum or set of signals correlated to a histogram in that there is looked for the minimum between two neighboring signal classes by mutual comparison of the stored signal values in a partial range of the histogram and there is stored as a separation threshold the characteristic of the thus determined channel characterizing the minimum, so that there can be differently evaluated signal values at different sides of such separation threshold. The invention is preferably used for particle analysis in haematology.