Josef Anton Hofmann


Josef Anton Hofmann was a speaker system designer. Mr.
Hofmann was the “H” in the KLH audio company. He is known for “Hofmann’s Iron Law.” Hofmann theorized that when woofers are mounted in speaker enclosures, the designer would have to accept that there are three trade-offs.

Iron law

Hofmann argued that the designer had "...three parameters that cannot all be had at the same time": good, deep low-frequency sound, a small cabinet size, and high sensitivity. Hofmann stated that designers could pick two of these three parameters, but in doing so, it would compromise the third parameter. For example, a designer who wants good, deep low-frequency sound and high sensitivity can obtain these goals, but they will have to use a large speaker enclosure. Similarly, if a designer is forced by space constraints to use a very small cabinet, and they aim to get good, deep low-frequency sound, the sensitivity will be compromised. A small cabinet with deep bass would need a very powerful amplifier.

KLH

KLH is an audio company founded in 1957 as KLH Research and Development Corporation in Cambridge, Massachusetts, United States, by Henry Kloss, Malcolm S. Low, and Josef Anton Hofmann. The original aim of the company was to design and produce loudspeakers in speaker enclosures.