Magaosi DQ4 IEM

I can think of a few headphones which have multiple dynamic drivers. The beast Roccat Kave XTD 5.1 comes to mind as an extreme case :) . I don't think that overlapping frequencies in drivers is inherently bad, even if they share the same LP/BP/HP filter. My biggest concern is how the ducts/vents are designed for them. On the review I posted above "1clearhead" mentions that there is a "vent" on the design. It's not clear to me if it's shared, exclusive, or what the internal looks like. Based on his review though, it didn't seem like the outcome was bad. Unfortunately it doesn't seem like this drop will succeed. I haven't placed an order, although I would if we were closer to the target.

Head-fi review: https://www.head-fi.org/threads/chinese-asian-brand-iem-info-thread.820747/page-1668#post-15081174

I mean the dynamic driver.has much wider frequency range , so no need two drivers , and the resister only crossover has no band pass ability., So the dynamics driver may overlap each other, which will create lots of problem. So I don't see many big manufacturer make multi-way head phone. For headphone the box design is a liar. There is no any theory for design a speaker box in a tiny space because the sound transfer speed and the air physical property.