Headphones with foam pads were intended to not have a seal.
I’m just tryting to say that creating a seal is a radical change.
If people are happy with modding to create a seal then all’s good.
I may be in the minority but I experience an open/vented front volume vastly differently from a sealed front volume. The Sundaras are unlistenable for me despite being superior in pretty much every way over the Grado Pestige line. I’ve been listening to Grados because they don’t seal.
I recently tried the HD 560S because I learned that many of the Sennheisers have a vented front volume. This has been a game changer because they give me an “unsealed” experience and also have a natural tuning. I probably won’t go back to the Grado’s.