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Most second-order RC active filters show a marked dependence on the gain-bandwidth product (GB) of operational amplifiers (OA's) when the to be realized is greater than 1 percent of GB and . Here designs are given that are virtually independent of OA's when GB and . Even for GB and , the center frequency shift due to OA's is less than 0.1 percent. This desirable result is achieved by designing filter amplifiers which have zero first-order sensitivities with respect to the time constant of the OA's used in the design. As a result, the filter transfer function has also zero first-order sensitivity with respect to . General criteria for such designs are given. Experimental results show excellent agreement with theory.