I haven't checked this for a few days due to a road trip to Michigan...
To me, there are times when I like a darker, easier listening sound, like when I am not particularly listening to music to get anything out of it, but as simply background noise. Then, there are times when I would like to have the ability to dissect the music - pick it all apart and see it for what it is (read Neo at the end of the first Matrix)...
Anyway, this is about sonic manipulation of Sennheiser to grant favorable effects to the end user. I have no skill in EQ, but that's kind of why I started this post. What I did was get the headphone response for the HD 558 from Headphone.com, and simply tried to inversely mirror the response on the EQ in order to try to equalize the sound. Now, the tools I used to try to accomplish this is nowhere near idea, I was left guesstimating with huge margins of error - but I thought I would throw it at you fine folks in the headfi community and see what we could collaborate with :)
So far the feedback has been an intensely interesting read. I don't think there is enough to say about the effect the brain plays in the perception of audio quality. For example, if I use the "treble" preset on the EQ the music sounds sharp overly intense - but after an hour of listening that way it becomes "normal" - and going back to the flat setting makes it sound like there is a pillow over my ears - the bass is bloated and all over the place, the detail is lost, etc.






















