Power supplies are more critical than you might think. A power supply in a stereo amplifier doesn’t just provide energy to let the amplifier function. The power supply IS the music that you hear.
It would be reasonable to think that the music signal comes into an amplifier, gets amplified, and then gets directed to the output jacks. But this is incorrect. In fact, the amplifier copies the music signal, and it is the copy that is sent to the output jacks. The “blank page” that receives the copy is the power supply signal. Once the music signal is copied onto the power supply signal, the power supply signal is then sent to the output jacks.
The power supply signal, therefore, literally becomes the music that you hear. This is one reason that the power supply is so important. It is why the capacitors producing the power supply signal are so important. And it’s one reason that Bob Backert invented the GreenForce™ power supply.