This article shows work that follows on from research by Toole et.al. The main point being that when given tone/EQ controls, (Toole's tests already compensated for speaker volume differences) a majority of speaker test listeners tended to make similar tone changes, and not ones that accentuated extreme tonal balance (adding/subtracting a ton of bass or highs). Read Toole's book/articles for details.
I have spent some time using iTunes' built-in EQ to adjust (crudely) for differences (volume and EQ) between commercial recordings. I used to reluctantly use the iTunes Soundcheck "automatic" volume leveling/compression option, but the volume still varied a lot between local iTunes music files created from different download/CD/streaming sources.
I primarily listen in Shuffle mode, so the editing/mastering volume/tone inconsistencies between recordings become really apparent. In the digital age, the "Circle of Confusion" is a now a significant issue for serious music listeners, unlike the olden days when we would put on a vinyl album or CD and adjust volume/tone before plonking down in the sweet spot.
It would be REALLY nice if the music recording/reproduction industry would settle on and implement some standards that curb the worst excesses in recording/editing/mastering that contribute to the Circle of Confusion. Toole notes that the movie industry was forced by surround sound technology being implemented in public theatres and TV/home settings to attempt to address this issue, but apparently the music industry has not done much for stereo listeners.
I get that musicians will always push sonic boundaries, but there is no reason for patently extreme examples to get past the recording/editing/mastering engineers. The bass in You Should See Me In A Crown is WAY over the top, and I like a lot of bass. Especially if it shuffles in before/after something like Breakfast In America.
I'm not advocating automated real-time compensation as the article suggests listeners may want, that's a bit of a cop-out from the industry not willing to set up a certification/monitoring framework for music recording/reproduction. I'm not a purist by any stretch, but I don't want some (another?) algorithm deciding what the musicians/engineers intended. "Hot" recording/mastering has been known reproduction problem since forever, but was nearly impossible to quantify, let alone control in full-analog. But now we have hifi digital, and that excuse no longer holds any water.
Imagine how much easier selecting/setting-up new gear would be if digital source material volume/tonal balance was reasonably standardized, instead of the "anything goes" situation we face now.
This is interesting research. I have found that as much as I have 'tinkered' with eq over the last 10 years of stereo listening, I've never been satisfied with my results. It's always the same thing for me: the speaker/headphone setup is generally too bright or lacks some bass so I want to make an attenuation. I usually mess around for a while then become mildy annoyed and dissatisfied with my speaker/headphone and move on.
In the end I have found and settled for speakers and headphones that I used for more pop/mainstream music whenever i'm in the mood for that sort of thing. I won't mention models but there are relatively cost effective solutions that can sound just about as good as I could think of for these genres. (Harman and Toole were directly involved in the production of one of said cost effective products, I will say that... )
On a related-ish topic. I recently spent a few hours weekend listening to some speakers in my setup. After a longish day of listening on and off I decided to give my ears a rest as they were feeling a bit tired. I am a professional brass player and had a concert that evening which was a combination of organ and brass music. There were some really epic moments and lots of huge crescendos with the brass and organ. In my tacet moments I really listened hard to some of the organ timbres, with the different stops and ranks being used. There were some REALLY bright strong sounds coming from these pipes but it wasn't at all triggering my ears to become fatigued. I actually wanted more and more, a bit like a nice seasoning or flavour that is kind of irresistible after your first taste. I'm sure there are a few reasons behind this - the sound was more evenly dispersed in the cathedral, not directional like listening to speakers.
I just makes me think that we're still quite a ways from being able to produce sound naturally so it doesn't fatigue one's ears. We're getting closer but we still have a way to go...