In order to check the theoretical results of a previous study (Lurie 1980 a) a 16-order 2-ehannel non-linear feedback system was designed and tested. The average slope of the feedback cut-off was — 20 dB/octave. The system was unconditionally (globally) stable. In the prescribed frequency band the attained feedback was 30 dB greater than the theoretical limit for a single-loop system. A good agreement with the theory of the previous study was achieved