The multi-channel case of using many anti-noise generators is much more complex than a simple single-channel. I once proved a nice theorem about the multi-chan

The multi-channel case of using many anti-noise generators is much more complex than a simple single-channel. I once proved a nice theorem about the multi-channel case, using Lagrangian multipliers and the theory of Gershgorin disks, which are what you get if someone upsets a Tower of Hanoi game all over your complex plane: https://en.wikipedia.org/wiki/Gershgorin_circle_theorem https://en.wikipedia.org/wiki/Gershgorin_circle_theorem