Hello, I'm looking into buying earphones (in ear) to use with my smartphone. I've noticed there are different materials for the driver housings - some are plastic, some are metal etc. Is there a noticeable sound difference? which type would suit me the best, if what I want is: -No heavy bass, and especially not muddy. -Clarity, especially vocals Should I consider BA and not Dynamic drivers? Also, on the same note, are dual driver IEMs better for clarity? Are they too heavy on bass? Thanks!