Isolating a specific noise

Hi everyone! I’m new here!

I’m having a problem with my project, and I was hoping you fine gentlemen can give me some advice/tips.

I attached a picture of what I am working on. In the picture I am viewing my audio file in SPECTOGRAM, and I am trying to isolate the more purple-ish section from the blue-ish section. I can’t use High/Low pass filters because that would remove some of the purple sections as well… Is noise removal the best way to go? I tried doing that but the purple regions got reduced as well… Any advice on how to do this?

Thanks everyone!

I think arriving with a conclusion of an analysis is premature. Post a clip of the sound before you did anything to it and describe the work.

Such as: “I recorded a lecture and I’m trying to remove air conditioning noise.”