How do you come to this conclusion? The measurements of the 502 Pro look terrible. Sinad is much lower than those above, Bill mentioned.
Really? Sinad is estimated about the same, as
@BillG figure is A-weighted, there is no direct comparison between two. Also look at distorion figures, there are few times worse in the case of D8 and D802 comparing to the FX502SPro!
D802 is FDA (fully digital amplifier). These amps chips are generally inferior to the chips with analog inputs, they are designed to be cheap. At the moment I can't make more comments on the other amps and I have no reason for researching, the last three look the best in my book.
Really?
"
Conclusions
I try to not get emotional when it comes to testing products but sometimes the test results either get me excited or depressed. And boy, was I depressed after seeing these results. The measurements here indicate that neither one of these amplifiers fit any definition of high-fidelity we strive for in this forum. The FX Audio FX502SPro is extremely cheap but in my book, is not a proper product. It has design issues and lacks power."
https://www.audiosciencereview.com/...opping-tp60-and-fx-audio-fx502spro-amps.5025/
Really. It was the first test Amir made with new equipment and he seem to become depressed with some minor design faults in FX-502SPRo. It caused that Amir didn't finish all tests, but results of tests he made are competetive. FX502SPro beat a higher priced (and generally well regarded) Topping D60 in all aspects: SINAD, distortion, except a total power.
Just look at the graph attached, how FX-502SPro presents agains all others: