I have Pioneer Premium IEM and on-ear headphones which are impressive! I thought they were at least twice as bad and I was wrong, they don't get close to 40kHz in any way, it sounds like the curve drops off by 20kHz, these are tiny drivers, they will put you in the go head. Very light and cheap feeling, I'm pretty sure it's nothing more than relabeled Chinese junk, the only Pioneer mark is on the mic cable. They really are terrible for the price. Headphones for $5.
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