I can't settle on an amp because I need help understanding what kinds of power to expect. I just want something I can listen to general music with and occasionally get loud with movies (bookshelf spks). Onboard power supply is a must. I apologize for having so many questions and for saying 'I' too much. Although I have most experience with general soldering, I have access to an SMT capable station.
1) What is the fundamental difference between a 2x30W and 2x100W amp? The 2x100W can reach higher amplitudes/loudness? Or just do so without loss of quality?
2) Why do 41Hz recommended transformer power ratings have VA units? I have some education in power factors but have only seen those units on industrial equipment. Can't I just use wattage ratings when searching?
3) Why do some amps require two voltage sources?
4) Where do people buy non-brick transformers? Generic X from Digikey? Are these hard/dangerous to wire for beginners (beginners to transformers, not general electronics)?
5) Is the transformer the only extra elec. component needed?