ATC SCM 150ASL measurements

[Vintage57]

I came access this printout during the move of a study/office.

I’m interested in comments on the graph and how it relates to what you have heard when listening to ATC’s

I believe it was produced in house by ATC.

 

[FeddyLost]

Looks like printout of max SPL sweep and/or power compression test.
Correlates nice with claimed 117 db peak SPL and borders of FR...
I have never heard ATC speakers personally.