Regulated Dual DC 12V DIY Electronic Circuit Diagram
This circuit can be used to create your own Dual power supply
What Exactly is a Dual Power Supply?
Some circuits require a dual power supply (eg-Op-amp ICs,pre-amps,power amps) to double the input voltage.
dual power supplies will have 3 outputs, known as (+)positive, and (0V) or GND, and (-) negative, example a TDA2030A(a hifi amplifier IC) will not work from a single rail power supply because it is intented to use only with dual powersupply.
The Circuit

So here is the easy to build dual power supply circuit, this circuit can output regulated 12V output with 1A current. The positive regulator is 7812 positive 12V regulator IC, and the 7912 is a negative 12V regulator IC.
This circuit can be used to power pre-amps and low power amplifiers if they need a dual power supply,
Note: Two heat sinks should be attached on the ICs to reduce heat and increase life