An electric stringed instrument, comprised of:
- a. a body with one or more hollow spaces under removable top plates and bottom plates covering said hollow or hollows, with a system of mounting one or more types of electromagnetic pickups, mounted between said top plates and movable under the strings, in a sound hole between the neck and bridge and between said top plates, said top plates having mounting slots running in the direction from neck to bridge adjacent to said sound hole, to which said pickups are mounted by a system of adapters specific to each type of pickup, with said top plates sized near said sound hole according to each type of pickup;
- and
- b. a system of electronic circuits to choose among all the possible humbucking tones from combinations of said pickups, including some non-humbucking tones when said types of pickups include matched single-coil pickups, said circuits both including and advancing related art from the family of inventions and patents that include this invention, that said system of electronic circuits are specifically of two types with three levels of complexity, all of which can be interconnected in cascade or tree form to produce a single output, either differential or single-ended with the low terminal grounded, including:
- i. a first type of circuit using switches, with:
- 1. a first level of complexity, which uses electro-mechanical switches to connect one or more pickups into circuits connected to an output;
- and
- 2. a second level of complexity, which include the first level and at least partially compensates for amplitude variations at the output, due to signal strength differences and phase cancellations between pickup signals;
- and
- 3. a third level of complexity, which replaces electro-mechanical switches with digitally-controlled solid state switches, including a programmable device to control them, and digitally-controlled analog circuits to provide amplitude compensation to the output, and programming to set the order of tones being switched according to some user-preferred and controllable sequence between bright and warm tones;
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- ii. a second type of circuit using analog circuits based on humbucking pairs, with
- 1. a first level of complexity, which linearly combines humbucking pair signals in a curved path through the humbucking pair signal space, which does not pass over itself or its inverse output to produce duplicate tones;
- and
- 2. a second level of complexity, which includes the first level and at least partially compensates for amplitude variations at the output, due to signal strength differences and phase cancellations between pickup signals;
- and
- 3. a third level of complexity, which replaces manual controls in the first two levels with digital switches and potentiometers, controlled by a programmable device, to automatically compensate amplitude variations at the output, and by programming to set the order of tones being switched according to some user-preferred and controllable sequence between bright and warm tones.