Explain what is a clean power amplifier?


Can someone explain what makes and define what a clean power amplifier is or does?  I have googled and searched the forum and haven't found a simple explanation to grasp. 

Thanks
trevanian
Clean power coming from an amplifier ,comes first from the electrical grid of the house....

Then it is of no avail to bought the best amplifier in the world without cleaning the electrical grid....

Costly solutions exist, but low cost one also....

When the power that comes from the grid is cleaner, a better instrumental timbre and a better imaging result naturally from the conveying signals...

Instead of thinking about how to embed their amplifier or any other gear, most think to buy a ready made solution... But there exist NO electronic component that is by itself the ready made solution to the complex triple embeddings....

« Noise contains silence like oyster contains pearl» -Groucho Marx
@trevanian my amps are clean i wipe them with isopropyl alcohol once a week
Clean power could mean class D as well. Used the least juice and best on the power grid.