These are just some very early impressions since almost nobody reviews the super cheap Koss products under $30 other than the KSC75 etc.
First impression from a Clip+ was that the bass was a bit bloated (not the Clips fault). I stopped using that immediately and switched to my Headroom Micro Amp and ODAC (both very neutral). I don't know if they'll sound as good with portable devices. Maybe an amp is a good idea? Remember..early impressions.
The sound is quite full and kind of warm sounding for a $18 headphone. There's quite a lot of bass, but not overkill. Except for the slightly boosted bass, it sounds fairly well balanced. Not like a studio monitor. These actually have more than enough treble so far it seems like.
With harsh garbage tracks they're a bit fatiguing in the upper mids/treble I think. It seems to not smooth them over at all and make them any easier to listen to.
I'm listening to the Nine Inch Nails song "Besides you in time" and am surprised how good these sound for $18!
They're more balanced sounding than the Philips Downtown I just got. More treble, less bass and more neutral mids. I don't have to feel like vocals are too shouty. Comfort is better too.
Yes, despite the Downtown retailing for $100, these are better.
First full sized $20 headphone i've heard that wasn't a piece of junk! These are even $12 online..crazy.
Not sure about build quality, but it's VERY plasticy. Well duh, it's $20. Comfort it's a 4/5 for now, but it may go downhill. The pads are not that deep at all and kind of small.
BTW I wonder if this uses the KSC75 driver? Probably not, but I should inspect it.
I also tried the UR-29 and UR-20 and this sounds much better than both of those IMO. I don't remember the UR-40 much. I'm also a fan of the UR-55 and of course the Koss Pro DJ100.
EDIT: I just noticed that my Pearstone Velour pads fit
So do the M50, M40 and V6 pads. The M50 pads would ruin the sound probably and make them too treble happy.
The Pearstone pads stretch a bit and give you slightly more room inside them.
EDIT 5000: I've been listening to these the last 2 hours(!!) with the Pearstone Velour pads. Ultra comfortable and the sound is impressive. Sounds better than many $100 headphones that i've tried. Right now it sounds quite well balanced, but with a slight tilt toward being a tad trebly.
Have a great weekend