"The top-middle bump causes terrible pain in my center head and it also doesn't go away soon."
I have had the same issue. My head would hurt a lot with the headphones on, but it would remain sore and tender for a few days! If I listened to the K701's till my head hurt - about 30-60 minutes. My head would hurt much quicker the next evening 5-20 minutes!
And my head was tender to the touch during the day.
Well, I couldn't stand the pain and bumps anymore!
I finally broke down and got out a sharp knife and some needle-nose type plyers and skinned that plastic piece of C^@P off of my headband.
I still think the leather is nice. So, I wanted to save it.
Plus.... I needed it for function!!!
But, here is what I found. The plastic liner has a combination of felt and foam type pads within the bumps.
It is (obviously) all bonded to the leather with adhesive - probably spray on, but maybe some sort of contact glue of some sort.
The felt was up against the leather, so those came off leaving a fairly clean glue residue - glue, but no fuzz.
The non-pad areas left a fuzzy foam imbedded into the adhesive remaining on the leather.
It isn't very pretty right not, but it is a hundred times more comfortable to me at this point.
I will probably go back at some point and put some type of foam/velour combo or similar nice material.
I will look around at other cans to get some ideas before committing to an option.
I think I can slightly spread the cans apart, tape and protect "EVERYTHING" and spray adhesive or roll on adhesive or whatever on the one side of the leather to re-bond a new "single" level (without bumps) piece of foam and material.
I am actually working on a lot of other projects around my house.
So someday.....
I will take my time to figure out what seems best. I know some foams are better than others as well and want to get a good foam.
I have some large enough scraps of "Poron" type foam that I purchased and used for a custom poker table that might work well.
Poron is VERY good at always returning to shape. It is used in some high end shoe foams and similar. But, it is fairly dense.
It is about 0.25" thick. I might combine that with a thin layer of softer foam (?????).
Since I apparently have more of a peak at the top of my head, I may try to shape the foam a little to accomodate my head - instead of contradict it like the original pad.
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