Good point about registers and I might have my octaves wrong but the notes that offend are, I think, from "F" to "A" above Middle "C". About in the middle of a Sopranos range. That's surely in the 2226 at about 650 to 1000 Hz.However, the annoyance is kind of a ringing which leads me to the overtones and that puts it mostly above 1600 Hz.
I ordered an inexpensive (