New driver? Mods? How to make these cans sound less muddy

[ElectricKaibutu]

I looked all over for on ear closed back headphones that had a list of features I wanted (one sided cable that's detachable, foldable, good build quality, comfortable, won't break the bank) and found my options were very limited. I ended up getting a like new pair of Urbanears Plattan 2s for $25. And they're great, tick all the boxes, except SOUND. They are a muddy, bassy mess. The worst part is how recessed the vocals are. The sound being good is kind of important for headphones, but because I like everything else about them, I want to see what I can do. I currently EQ, but I still have issues with the recessed vocals and I'm basically locked into using my rockboxed iPod Video if using EQ. I just want them to sound better so EQing would become an option, not a necessity.

I was thinking I could try different drivers. The Plattan's have 40mm drivers. Maybe I could order a pair of Sennheiser Urbanite drivers, but looking at the article on InnerFidelity, it looks like they have their own internal housing and might not fit the Plattans. There are roughly 3000 different drivers on aliexpress to choose from, or there's also the Dayton Audio CE38MB-32 which seem middlingly recommended.

Or maybe mods? I've seen articles about taping up holes on the driver to decrease bass. I don't want to drill any new holes on the outside, since they need to stay sound isolating for work.


tldr;

So what do you think? How much luck do you think I could have with new drivers? Or would they probably not sound much better due to how the housing is tuned? Any driver recommendations? I'd rather not spend more than the $25 since that was the price of the headphones. Alternatively, any mods you would recommend?

 

[ElectricKaibutu]

I popped them open to take a look at what I have to work with.

Easy to dissemble with three screws.

There is a small hole on either side of the headphone near the hinge. Covering the hole doesn't seem to affect the sound.

I popped the backs completely off. That made the treble worse.

After testing I think it's the pads that are causing the boomy bass. They might be too thick. The problem is, I like that they're thick for comfort reasons. I think I need to find a way to decrease the amount of empty space created by the pads. Maybe by adding a thick piece of foam? But I'm afraid that will muffle the sound.