Most DC power cables, at best, provide 12V at 500mA. Many of the brands putting out DC power cables use too thin of wire to have the voltage and current maintained from one end to the other. So, it might be 9.6V if you were to measure the voltage at the power supply.

Still, when you re-measure at the end of the power cable where it connects to the pedal, it ... Read More

Most DC power cables, at best, provide 12V at 500mA. Many of the brands putting out DC power cables use too thin of wire to have the voltage and current maintained from one end to the other. So, it might be 9.6V if you were to measure the voltage at the power supply.

Still, when you re-measure at the end of the power cable where it connects to the pedal, it could have dropped 0.5V or more because the wire is not thick enough to maintain the voltage without adding resistance to the line, dropping the voltage.