It’s all just an issue of how much the frequency responses vary over a given range of measure
+/- 1.5 dB isn’t “flat” but it’s a lot flatter than +/- 3 dB, so on and so forth. I guess technically they should be called “fuller range and “flatter” response, but it’s all relative to what it’s being compared to. Other issue is different brands can use different spec, so what’s more or less flat at a given intensity level can change compared to a different product measured at a different intensity level.
I’ve had lots of guitar cabinets, lots of studio monitors, and all the major “frfr” powered monitor options (save for a xitone open back) and they all sound more the same than they do different. There is no way I could yell blindfolded if I was hearing a xitone or a clr etc. a/b them and there is a difference when you switch but I don’t think any “frfr” has enough of a sonic signature to pick it out blind.
Another interesting point is it seems on modeler forums especially there are lots of “cab in room fans”. Often times those folks seem to just post on TGP about how they hate anything that isn’t a tube amp lol...
Anyways, I get lots of people like the sound of their amp/cab in their bedroom, rehearsal space etc. I spent my teen years with a jcm800 and 4x12 in my bedroom. Mattress on floor, black painted walls, Xmas lights on the ceiling et al.; typical late 80s early 90s teen guitar player who cranked that rig everyday after school. It’s all good if that’s what your still into.
But, so many folks always seem to be on a quest for album tones. They dont want to sound like Slash live, they want to sound like the appetite album. No one wants pumpkins love tone, they want Siamese Dream wall of fuzz etc etc.
This seems ironic to me then because album tone obviously is a polished recorded tone, yet people always try to create that with their amp cab and pedals. Myself included, having spend an insane amount of money trying to find a Siamese dream fuzz, or a Gilmour big muff etc
But I’d stick those pedals in frint of my Lionheart or DRRI etc and then feel it doesn’t sound right, it doesn’t match the albums.
So it seems like a lot of people want to sound like an album, Steve Jones Anarchy tone for example, but no one wants his live tones (not that they are bad mind you) but we, collectively speaking” also want the cab in room experience, saying we prefer it to the modeler IR sound, yet the modeler IR sound is the album tones...
So what are we chasing ? Sound if a favorite album growing up? Sound of our first tube amp cranked up after school? Sound of our favorite guitarist playing live during our favorite live performance we’ve seen?
It seems it’s essentially the thril of the chase, and simply wanting to be inspired to play more guitar. I got excited about switching rigs last year, went out and bought a Lionheart and nearly every pedal I used to own, gas’in from Bjorn’s Gilmourish reviews more than anything. Every $200 fuzz being the “key” to sounding like Gilmour. Never happened lol
In the end, I think it’s often just a grass is greener issue, we play our amazing modeler and think we are missing amp in room, we play our amp and feel it doesn’t sound like the album, so on and so forth.
I can only speak for myself but my hobby isn’t just playing guitar, it’s also chasing tones, talking about guitar and gear. I probably spend as much time reading reviews, watching clips, searching eBay etc as I do playing my actual guitars.