What is “negative feedback”?
Top of Page A: It is a design method used to reduce THD in the output signal in which a portion of the signal from a later amplifier stage is “fed back” to an earlier stage (or to the same stage) in such a manner as to subtract from the input signal and is usually measured in dB. Although it is advantageous in reducing distortion to lower levels, it degrades the overall sonic quality of the output. The more negative feedback is applied to the circuit, the more the overall sonic quality is degraded. Part of the sonic virtues of the TubeDriver BLUE amplifiers is that all BK Butler designs employ ZERO negative feedback.
