Yeah guys. Comparing frequencey response graphs from two different sources is a big no no. Nothing useful in doing that. The only thing we can probably say is that the 7520 would probably have a bigger bass response. As for HeadRoom. I doubt they'll ever do a graph of the 7520. It's been out 2 years now? They won't get permission from Sony to sell it so.... unlikely. If you want to really see measurements you can send it out to Tyll and see if he's willing to take some measurements.
Edited by M-13 - 1/6/14 at 12:57pm