A combo sensor system comprising: a substrate assembly comprising a top substrate and a bottom substrate spaced apart from each other; a diaphragm assembly comprising upper and lower diaphragms (38, 40) spaced apart from each other, wherein the upper diaphragm and the top substrate are formed as a monolithic structure and the lower diaphragm and the bottom substrate are formed as another monolithic structure, the diaphragm assembly and the substrate assembly defining a driving system; an acoustic transducer (30, 130, 230, 330, 430, 530), the acoustic transducer (30, 130, 230, 330, 430, 530) comprising: - a first electrode element suspended to a first part of the upper diaphragm via a first isolator and a second electrode element suspended to a first part of the lower diaphragm via a second isolator; a pressure sensor, the pressure sensor comprising: - an electrode element assembly comprising an upper electrode element suspended to a second part of the upper diaphragm via the first isolator and a lower electrode element suspended to a second part of the lower diaphragm via the second isolator; and an insulator structure assembly comprising an outer wall and an inner wall, wherein the outer wall is formed around circumferential portions of the upper and lower diaphragms (38, 40) so that the first and second electrode elements (44, 46) and the upper and lower electrode elements (44b, 46b) are enclosed by the outer wall of the insulator structure assembly, and wherein the inner wall is formed between the first and second electrode elements (44, 46) on one side of the inner wall and the upper and lower electrode elements (44b, 46b) on another side of the inner wall so that the pressure sensor and the acoustic transducer share the inner wall of the insulator structure assembly. a substrate assembly comprising a top substrate and a bottom substrate spaced apart from each other; a diaphragm assembly comprising upper and lower diaphragms (38, 40) spaced apart from each other, wherein the upper diaphragm and the top substrate are formed as a monolithic structure and the lower diaphragm and the bottom substrate are formed as another monolithic structure, the diaphragm assembly and the substrate assembly defining a driving system; an acoustic transducer (30, 130, 230, 330, 430, 530), the acoustic transducer (30, 130, 230, 330, 430, 530) comprising: - a first electrode element suspended to a first part of the upper diaphragm via a first isolator and a second electrode element suspended to a first part of the lower diaphragm via a second isolator; a pressure sensor, the pressure sensor comprising: - an electrode element assembly comprising an upper electrode element suspended to a second part of the upper diaphragm via the first isolator and a lower electrode element suspended to a second part of the lower diaphragm via the second isolator; and - a first electrode element suspended to a first part of the upper diaphragm via a first isolator and a second electrode element suspended to a first part of the lower diaphragm via a second isolator; - an electrode element assembly comprising an upper electrode element suspended to a second part of the upper diaphragm via the first isolator and a lower electrode element suspended to a second part of the lower diaphragm via the second isolator; and an insulator structure assembly comprising an outer wall and an inner wall, wherein the outer wall is formed around circumferential portions of the upper and lower diaphragms (38, 40) so that the first and second electrode elements (44, 46) and the upper and lower electrode elements (44b, 46b) are enclosed by the outer wall of the insulator structure assembly, and wherein the inner wall is formed between the first and second electrode elements (44, 46) on one side of the inner wall and the upper and lower electrode elements (44b, 46b) on another side of the inner wall so that the pressure sensor and the acoustic transducer share the inner wall of the insulator structure assembly.