Learn to recognize the brands, and so to know if quality parts have been used in the circuit
A electronic parts index picture or circuit board. - Hifi Audio
One of the many images of this product. Discover the front and the rear panels, and the pcb circuit.
Here you can find some of the best and most used manufacturers of electrical components for circuits. An high quality electrical part has an higher reliability and also a lower distortion, so a better sound. No brand parts are used only to economize.
Obviously a quality parts doesn't make a good circuit, but a good circuit can be maximized via quality parts. Surely it is most liked to have durability from a reliable manufacturer, than from a generic one.