Vintage Hammond A-100 Vintage Organ With Bass Boost and Bench + Leslie 145/147"The best hammond B3's are A100" Totally refurbished and refinished jamming a100 organ. Used for one album. Leslie speaker included The Hammond organ is an electric organ invented by Laurens Hammond and John M. Hanert and first manufactured in 1935. Multiple models have been produced, most of which use sliding drawbars to vary sounds. These organs were less popular, and the company went out of business in 1985.