i have very often a good laugh in shops, when i look trough holes in those homecinema 7,1 100w receivers.Here's one example of blatant lies.
Surround receivers are what's hot now in the consumer market. I've had two in my lab; one a Sony and one a JVC. The Sony was junk no matter how you look at it- no setting of the tone controls would provide even marginally acceptable sound. The JVC was a lot better, but...
Both are rated 80 watts "RMS" times 5. The Sony couldn't come even close to 80 watts times 2; the power supply just collapsed. It did provide 80 watts times 2 with a pulse signal, but not a steady state signal; it's closer to 26 watts times 2.
The JVC did provide 80 watts times 2 steady state - pretty good. But forget about 3, 4, or 5 channels - it'll never happen.
These are two examples of blatant deception. I think that anybody could read a Wikipedia article and figure out how to verify these marketing claims. They count on ignorance, in my opinion.
There's more, but it tells the same story. Power output claims = blatant BS.
smaller trafo than mine 250va lundahl
perhaps they passed rms tests, but only one canal playing at a time !