The Damping Factor Debate
by George L. Augspurger, JBL Inc.
Electronics World, January 1967

What do numbers really mean and do high amplifier damping factors have a noticeable effect on performance?

Some amplifier manufacturers have introduced circuits that have much higher damping factors than conventional units. A high-quality "traditional" vacuum-tube amplifier can be expected to have damping factor ranging from 10 to 20, but some of the newer transistorized units boast of damping factors greater than 1000. Moreover, advertising and promotional literature for these models explains that the damping factor is a sort of figure of merit indicating the degree of control which the amplifier has over the loudspeaker. The higher the damping factor, the more accurately the speaker is controlled and the better the performances. Is this right?