While still many audio enthusiasts favor linear power supplies for their circuit, switching mode power supplies (SMPS) are used more and more. They have several advantages to linear power supplies. Not only are they usually more efficient, but also the switching frequency can be far outside of the audible frequency range. Even though you can use the circuit diagrams in the data sheets of available ICs, you might want to learn a bit more about this kind of circuits. In this case, the Coursera course “Introduction to Power electronics” is the right course for you. The course started today and you can attend for free.