When I was looking into a different squig.links I felt it quite strange, why does the Oxygen graphs don't look the same. Maybe I am completely wrong and it is related to a different measuring devices, but from my point of view it looks like the tuning of the Oxygen has been slightly adjusted and now is almost exact as the Hana 2021. As it can be seen from the first measurements made by HBB and Crinacle in 2019. While the Precogvision's graph from early 2020 shows an elevated sub bass region. The same can be seen in the Super*review's graph.
HBB's graph:
Crinacle's graph:
Precogvision's graph:
Super*review's graph:
HBB's graph:
Crinacle's graph:
Precogvision's graph:
Super*review's graph: