да есть у них синглы
а трансформатор куда ни относи, а повышающие трансформаторы там для того чтобы повышать.
... и добавил:вот их патент:
"Abstract
a primary winding creating a primary current from a disruption in the magnetic field by the strings, the primary current creating a primary electromagnetic flux, and
at least one secondary winding spaced below the movable strings and adjacent to the primary winding and
transforming the primary electromagnetic flux into a secondary current which is passed out of the stringed musical instrument".