So why is a guitar pedal's power connection actually center negativ and not center positive like almost all other electronic appliances?
A 9V DC center-negative power supply is the de facto standard for pedals.
Most electronic devices and their power supplies have center-positive polarity, so why do pedals have center-negative polarity? Because many pedals work with either a battery or a power supply; and, to preserve the life of the battery, it is disconnected from the circuit when either (1) a power plug is inserted or (2) the input plug is removed. This is accomplished by connecting the battery's negative terminal to the input jack's ring contact and the battery's positive terminal to the sleeve shunt on the power jack. When the input plug is inserted, it completes the circuit for the negative battery terminal. When a power plug is inserted, it breaks the circuit to the positive terminal of the battery. Power jacks do not have a shunt for the center (pin) contact, so a center-positive power supply would not work in this type of circuit.
Add comment
Comments