Hello Craigvmn. All the numbers can be intimidating, especially when newer, younger writers, with no real knowledge and eager to please their bosses, write rubbish with is filled with pure rubbish and misuse of technical terms. For instance, many preamps are being advertised as Class A. All preamps are Class A. This means the output devices produce a faithful replica of the input, only larger in some way. Other classes of amplification produce altered, non accurate versions of the input. Class B uses two (or more - an even number) outpur devices one producing an enlarged version of the positive going part of the input. enlarged, and the othe the negative going portion of the input, suitably enlarged. These two get added together and fed to the output device, usually a speaker. The advantage is: less power gets wasted and two output devices can produce four times the output power compared to what one of the output devices could produce on its own, by itself. Class AB (there are several forms) is a combination which produces less inherent distortion than Class B. There is a Class C which is used in radio tranmitters. Class D is another animal entirely and not worth discussing here.
You have purchased very good merchndise and may be suprised to hear that sound is a very odd form of energy. We humans can hear a mosquito flying in a room several feet away, a very small amount of power. Standing at Niagra Falls, the falling wter creates a great deal of sound energy. It vibrates our clothes, but it doesn't kill us. We hear on a logrithmic scale (spelling may be off). Most people can barely detect an increase in loudness of 3 db. An increase of 6 db is not difficult to notice, but is small. That 6 db represents 4X the power of the sound. A 10 db increase requires 10 times increas of power, but it doesn't sound much louder. As a result, most people don't use much power. Only when the drums go BOOM does the amp need to do serious work. Engoy the music! You are not likely to heart any distortion in your listening situation. Relax, life is too short to waste on worrying.