Cork, first I have to say that one can never judge performance by a few curves. However, I have the benefit of being able to leverage my experience with various Axioms, in my rooms, against published curves. So I feel somewhat qualified.
I have never tried the M22. But, knowing how the M2 performs in my living room, and looking at the M22 vs M2 curves, I would place a strong bet I wouldn't have to move the bass from neutral. If I wasn't using a sub, I'd likely have to boost the bass a bit. Note the M2 does have a bit of a bump between 70 and 100 Hz. The M22 doesn't.
Do you have the M5 a few feet away from the front wall? Do you have them crossed to a sub? I think Trevor has them in a similar-sized room, a few feet from the front. It also depends on how lively your room is too. I can say the M5OW are much better than the bookshelves in my living room. I turn down the bass on some tunes but not nearly as much as the bookshelves.
Another possibility is Axiom has been messing with the M5 curves since I got mine but that's just speculation on my part.
Regarding curve interpretation, these are the curves I'm looking at:
M80:
https://www.axiomaudio.com/pub/media/catalog/product/m/8/m80_freq.gif660:
https://www.axiomaudio.com/pub/media/catalog/product/l/f/lfr660.jpgJust look at the smoothly declining curve of the 660 in the bass region. It is so free of the twin, 1 octave, low Q resonances the M80 displays.
Now look at the M100:
https://www.axiomaudio.com/pub/media/catalog/product/m/1/m100_freq_graph.gifSomeone at Axiom (Andrew?) ripped their hair out trying to achieve that kind of performance. No resonances there.
Feel free to examine the passive and active LFR1100s too. Use the active as a frequency response reference for all others. After hearing the v4 M2, M3, M50, M5, M100 and the active LFR1100 in two rooms in my house, I can unequivocally attest the active LFR1100 is perfect. PERFECT!!!
The actives are perfect because their listening window and sound power curves ride on top of each other yielding an absolutely perfect directivity of 0 dB - across the entire range!!! And do you see any resonances? No. That's because Ian "erased" any resonances that show up in the spatial curves using the DSP.
Now compare the listening window and sound power curves across the M80 and passive and active LFRs. See how the directivity improves with the LFRs? And how it's perfect with the actives?
Why is directivity important? Because a directivity of 0 implies an omnidirectional speaker. And any speaker which is omnidirectional, with a smooth, declining response of 3dB per decade, is going to sound good in a room in the band where the speaker dominates the room. This cutoff point is called the Schroeder frequency. Below that frequency, the room dominates. In your living room, that's about 80Hz.
Now why is the 3dB per decade important? Because the Schroeder frequency isn't a hard cut-off. In the midrange, the room and speaker compete for dominance. If you make the response flat, you'll get a boost and that will make the material sound unnatural. This is what I don't like about the active Bryston curves. They've gone for flat response. Sure looks good on marketing material.
Now look at the lfr bass response. See how it's a smooth, declining curve? That's the speaker saying, "Room, I know you're in charge. Boost my output, baby!" And OMG, is it ever right on the actives!
Getting back to bass, it's terrifically important. Most of the problems I had with M80v2 were bass-related. Not good bass screws up the rest of the response.
Now you might say, " So what? I'll use my processor to do auto-EQ." But here's the thing. EQ can't fix bad directivity. And remember directivity is important so you can hear a large soundstage with diffuse yet excellent imaging just like a real performance.
Or you might say, I'll use a sub. That may help but a speaker like the M80 will continue to pump out the bass because it's output is not steeply cut off. Those two resonances will still be there, BTW.
Axiom is telling you exactly what you're paying for. It's all right there in the curves. It's also important to note the character of the soundstage and imaging is similar for all products. And all this is achieved with the same drivers and similar cabinet design across all models.
Why statues of Ian and Andrew are not erected at the AES is absolutely beyond me. Harman has been struggling to produce this feat for decades with their fancy labs and Ph.D.s and two guys in shorts and sandals in the middle of a Canadian forest did it with no pomp and circumstance.