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The creation of tunable high order filters in which high accuracy of returning (the linear relation between the analog or digital control signal and the filter parameters) and the stability of the frequency characteristic shape in the whole tuning range must be assumed is a complicated problem. Filters on integrators enclosed by feedback in which the principle of changing the integrator time constant is realized by multiplying the input signal by a coefficient proportional to the analog or digital control signal correspond to these requirements. Analog multipliers or multiplying digital-analog converters can be used as tuning elements. The authors discuss the diagram of a universal second-order linkage with cutoff frequency tuning or selection as a function of the output to be used.