So I decided today to take my friend's Dayton IMM6 to take some measurements and see what was happening with this MOD (black with cotton/foam) that I have been talking about for so long. Since I couldn't have much time with the Dayton, I decided to take Rikudo's favorite filter (pink) to make a little comparison and see what was happening without anything:
- Both of them look similar, but the black filter has some obvious peaks in the high region.
The black filter MOD vs no MOD:
- As expected, all those peaks in the high region has been toned down; the biggest 4k - 4.5k peak has been toned down. Besides that, there is a weird thing happening: with the MOD on, the high mids between 500 - 1k has slightly been elevated, making it almost even to the peak near 3k.
The black filter MOD vs pink filter:
- To my surprise, on the black filter, the highs has been toned down to almost the same level of the pink filter, but it maintains the same high mids 500 - 1k boost. I have a feeling that somehow the MOD mutes partially the decibels coming from the single electropiezo, making the 4 BA drivers timbre more prominent on the mids. For some reason I have felt that the timbre has been improved.
Out of curiousity, I decided to try the MOD on the pink filter to see if what I felt (electropiezo getting partially muted making the BA's more prominent) was correct or if it was a "black filter thing"; first, pink filter MOD vs no MOD:
- It happens to be the case: highs toned down and mids getting elevated. I didn't feel that this MOD was suited for the pink filter because it erased completely the airiness of the highs and made the overall sound way darker.
Pink filter MOD vs Black filter MOD:
- Proportionally speaking, it was the expected case with no prominent peaks on highs and an almost even high mids with highs. The only difference here is that on the black filter we are maintaining the airiness of the highs:1k - 4k are still noticeably above the low and the mid region in comparison to the pink filter here.
It wasn't that much of a hassle doing this, but I think this helps a bit with the problem that some people may see with the treble spikes. Besides taming downs those spikes, I still think that there's a meaningful improvement with the MOD on in many aspects, so I encourage everyone trying it out since it is removable.
Thank you for reading.
I want something on the bright side and as I understand with blue filters it should sound bright and clear? As these went in price significantly since releas it looks like a bargain now 
