Had only the Onkyo TX-SR 308 and Harman Kardon to boxing gained. The 308ér I missed but then the last Watt reserves and had then decided to use the TX-NR 509, and I can only say what a difference. First clear to the 308 more power you also noted. But the surround effect and the sound is not comparable with the gigantic and 308ér absolutely. Have been measured with Audyssey, then raised all level values by 5 dB and am now really excited about this receiver. BluRays with HD audio sound just awesome. Man now feels really right in the middle. With Internet Radio I have no problem with the last update and running smoothly. Finally a receiver of excited me really. Strong buy recommendation and would if I could give more than 5 stars. ONKYO conjured again for such a price, as the one or the other manufacturers should even learn a lesson it.