are your mains angled inward or straight out? I found by adjusting my 80's further away from the side and front wall, and playing with toe-in, it helped that dip, as did the bass traps.

I'm heavily toed in right now to nail the image dead center. My room is small, 1700 cubes I think, in case that matters.

It's nothing a set of M80s can't fix

With the downloaded calibration settings, the RS meter is good to about 3000hz.

Mojo was heavily toed in as well and found he liked his M80s even more with just a little toe-in.

Thanks, that's just what i was hoping for.
[runs off telling the wife to fire up the car, "got to get a new microphone!"]

I had read that the RS meter was good to around 2000Hz so that agrees with what Jay wrote.

That dip at 70Hz is common in our rooms and often relates to a room height mode. Corner bass traps may help and you can also try traps above the listening position (didn't make any difference for me though).

Both corner traps and thinner (2") traps at first reflection points should help with the dip at 300Hz. Changing speaker position can also help here.

3000hz?????????? Oh, I have a mess on my hands. I have not even run it that high. I doubt it will get better.

Charles, reflections from room surfaces cause partial cancellations at roughly a quarter wavelength from those surfaces. The dip around 70Hz may be a wall bounce at about a four foot distance(1130 ft. per sec/70 Hz= 16 ft.). Are your speaker drivers about four feet from one or both walls? The dip around 280Hz appears to be a floor bounce similarly calculated arising from about a one foot distance. You need to move your walls and floor.

I agree Jay, Zimm I would experiment on the toe-in angle. Having them aimed right at you narrows the soundstage overall width. Like Mojo, I used to do the same as you. I have found pointing them at a point about 2-3 ft behind me gives me a much better sound stage overall where instruments take of the whole width, and the voices are dead center, appearing to come out of the center channel, as they should. Probably will help your graph dips. Also, you don't want the drivers the same distance form the side and front wall.