Very interesting topic, one which I've spent hundreds of hours trying to make sense of. I've read Dr. Toole's excellent book, read most of his insightful posts here and watched several of these interesting discussions from afar. I'm not one to decide my beliefs over some philosophical thinking, I like to test theories myself - to the best of my abilities at least.
The first step I did was to buy the best speaker I could that suited my needs; the Kii Threes ended up being my choice due to different constraints.
Those are designed with the Harman research in mind, aiming for neutrality.
I placed them in the worst kind of conditions - a scandinavian home where furniture is illegal, walls are made of empty concrete or glass by law and no wall-to-wall carpet because we scandinavians die randomly when exposed to dust and germs.
On top of that, I placed them asymmetrically with one in a corner and the other with no side boundary for miles.
Surprisingly, this sounded nothing like neutral, dynamic, crispy, nice or comfortable. A revelation considering the claim that rooms are irrelevant, so I decided to take my speakers with me to different rooms. Both smaller and larger than my own. I could hear that it was my speakers most of the time, but the perceived sound quality was so much better when I placed them in a bigger room with far more space around the speakers.
Somebody somewhere lied about rooms being irrelevant!
I decided to experiment with a few absorbers behind my head and it sounded much better. Clearer, softer, snappier, warmer and more comfortable.
Frequency response remained the same, impulse-response/decay/RT60 and clarity did not.
It was clear to me that whatever happens in the time domain is important to my enjoyment of listening to music. Here's a selected few comparisons from before any treatment to how it looks now after placing 4 x 4 inch RPG Absorbors behind my couch and 4 inches insulation +
Ecophon plates on the ceiling;
If anyone want to argue whether or not this kind of difference plays any role in perceived sound quality, go right ahead. If you think it doesn't, you're dead wrong. Same room, same speakers, same placement. Just different materials in the first reflections on the ceiling and back wall.
So for me, the first part of the equation is tried, tested and concluded with. Even with good speakers the room will affect your perception on sound quality. The next part of the equation is, of course, room compensation EQ, which is a more difficult topic IMO.
Being a nosy individual, I have tested quite alot, both before and after room treatments. I have the luxury to have both Dirac Live and Audiolense on my computer and can easily switch between the two, and I'm also using Minidsp 4x10 HD with parametric EQ only - and can buypass any EQ as I see fit.
So many hundreds of graphs have been made and analysed, so many different filters, target curves and cut-off frequencies have been tested and re-tested. Want my opinion?
- Audiolense is faster, simpler
and have more fiddly-stuff so you can mess up everything in so many ways. More powerful software with more possibilities.
- Dirac really needs you to measure multiple points in space with sufficient distance, otherwise the correction will be way too much and will look like this;
Blue = Dirac single point measurement correction
Red = Dirac after room treatments with 9 point sofa measurement
Green = Dirac before room treatments with 9 point measurement
1/24 smoothing
- As we see, Dirac will not over-compensate when used properly. In the red graph I placed the microphone stand stupidly so that the high frequencies show alot of reflections from that. I fixed that mistake later on, but can't find the measurement for that. Notice how similar the red and green graph is, the green is before ceiling treatment. Placement is not the same, seating position shifted about 20 cm.
- Both Audiolense and Dirac can make your sound worse than no EQ if you try, but very difficult to make things worse under 250 hz.
- Both Audiolense and Dirac make very little audible changes over 500 hz compared to my PEQ-settings with Minidsp, but Audiolense sounds better full-range than limited to 500 hz. Dirac sounds flatter and less dynamic.
To those of you who suffered through all of this, thank you. All I wanted to say was that room matters and EQ can be good for you. But buy better speakers anyway!