Quote: I thought NP had patents on the floating bias CCS. From the other post, agreed there is no such thing as no feedback, but so many people use the term to mean global feedback. There are so many types of feedback after all. Quote: How does the Tao work? It is everywhere, and nowhere. He who talks about it the most knows the least. "Zen" amplifiers are simply amps that are very simple. They are reduced to the absolute minimum of parts. This is in contrast with more common "more complicated" designs. Both schools of design have their advantages and disadvantages. Zen amps are easy to understand - with only a few parts someone with a bit of electronics knowledge can "walk around" in the circuit, and see how things work quite clearly. Ask a "zen amp" builder to explain how his amp works and its easy! The disadvantage is that they don't usually have much (if any) global feedback so to get good SQ they need to use very specific parts - thus the funky transistors. Even with great parts they still dont usually put up measurements as good as more complicated designs, but there is still a certain sound that they often make - a lot like simple tube amps. More complicated amps are much harder to "walk around" inside the schematic. Ask 95% of the people who have built a B22 to explain how it works. They don't know - just put the parts in and pray. The advantage to more complicated amps is that they usually design around feedback which allows the use of "who really cares, fix it with feedback" parts. Considering that the world in general is a "who really cares, fix it later" kind of place these days its a lot easier to find parts for this kind of amp. The disadvantage is that when you really look at it, your using feedback to polish a turd.