Wikipedia
Therevox builds custom musical instruments in Ontario, Canada. The company focuses on continuous-pitch instruments and is known for building a modern analog synthesizer inspired by the rare Ondes Martenot.
First commissioned in 2004 to build modern version of the Electro-Theremin as used by The Beach Boys on their 1966 single " Good Vibrations", only 12 of these instruments went to musicians and studios in North America and Europe. In 2010, Therevox was commissioned by Montreal's Breakglass Studio to design a new instrument that would combine the Ondes Martenot's au ruban and touche d’intensité interface with a dual oscillator analog synthesizer similar to the MiniMoog. The design included a built-in Spring Reverb and this prototype became the ET-4 model that has been available since 2012.
Some users of the ET-4 include The Besnard Lakes, Belle & Sebastian, Suuns, Team Me, Floating Points, The Gertrudes and Jason Isbell and The 400 Unit. The instrument has been a feature of OneRepublic's Native Tour and the ET-4 has also been used in movie soundtracks including the horror film, Nurse 3D, starring Paz de la Huerta and the Salvatore Ferragamo inspired "White Shoe".