First REW measurement

Hi all, just took my first REW measurement today..... interesting to say the least. Are there any good sites that you guys know of that work through how to address the dips and peaks in laymens terms?

I've read plenty on how to take the readings but not much about how to get close to the unoptainable flat line.

Like are using lots of filter a good or bad thing? How much gain is too much? Simple things like this.....

Thanks Dave

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