The history of Earth Sound Research (ESR) is not definitive by any means, but several people have weighed in with their information and experience. ESR was started as an amplifier brand by ISC Audio in Huntington, NY, and the two owners were Marc Neumann and Dave Garrett. ESR amps were all copies of popular brands especially Fender tube amps and Peavey solid-state models. ESR never had their own factory or engineering department and all amps were built by subcontractors at various locations. However, ESR amps were built much cheaper than their Fender and Peavey copies, and they had a lot of problems with amps not working. The output transistors in particular were built cheaply and they failed often. At one time, Peavey was going to sue ESR because of their design infringement, but they told ESR to change their design as it was cheaper than taking the small company to court. Andy Fuchs of Fuchs Amplifiers actually worked at ESR for a year in the early 1970s
There is also a lot of speculation that ESR and Plush Amplifiers are one in the same company. The theory is Plush started out building amplifiers in New York, they built a second factory on the west coast in Los Angeles, and throughout the east-coast company going under the amps in the west-coast were renamed Earth Sound Research. Currently there is no proof that ESR and Plush were the same company, built the same amps, or operated in the same building. There seems to be a lot of crossover between these two names, and any additional information about Earth Sound Research can be submitted directly to Blue Book Publications.
Amplifiers and speaker cabinets previously produced in the 1970s.