This is the more precise term for what we loosely call “the amount of negative feedback.” Let's take a hypothetical audio amplifier with exactly one integrator (see Box 1) and plot the various ...

Figure 1: A system with negative feedback. The closed loop transfer function is: When 1 + G(s)H(s) = 0. the system is clearly unstable. ... And the phase of the open-loop transfer function equals the ...