> Do expensive amplifiers have noticeably lower white-noise than the standard amp? I'd say amplifier topology matters more than absolute noise figures. For ex

> Do expensive amplifiers have noticeably lower white-noise than the standard amp? I'd say amplifier topology matters more than absolute noise figures. For example, you can build a 2kW class D amplifier that fits on a PCB weighing ~1lb. A 2kW class H amplifier is going to weigh over 40 lbs. Why would you ever want the one that weights 40x more and likely costs more as a result? The numbers are the same? Maybe even the THD is lower on the class D... The reason is the path the electrons take. In class D, there is a finite/discrete amount of energy available per unit time. The computer knows precisely what these limits are and controls the signal accordingly (clips/attenuates). In class H, there is a gigantic toroidal xformer that is responsible for directly stepping the raw line voltage to required DC rail(s) which then goes straight to your loudspeakers by way of basic mosfets. There isn't a discretized energy mechanism involved anymore. The entire chain is analog. As a consequence of topology and other factors, certain types of program material and loudspeakers can perform substantially better than otherwise possible. If you are looking to set up a system with ridiculous LFE that extends well-below 20Hz, class D amplification is probably going to get in your way.