The peaks at~3khz and ~8khz (or dip between, depending on how you look at it) I’d assume. A 5dB difference between ~3khz and ~4.75khz isn’t great. And that peak at 15khz,… could be a pretty big problem for some. It’s not enough reason not to buy it but it’s enough to give me pause.
Here’s a graph posted by another headfi-er (8th post down from this linkhttps://www.head-fi.org/threads/the-discovery-thread.586909/page-4365)
It’s not much different but for whatever reason looks a lot better to me. And look at the channel matching,… left and right are identical nearly all the way through. Should have one heck of a center image