Pros - Sounds big, compared to absolutely worse models.
Cons - 30-60hz deep bass is weak. Treble is extremely harsh, comes amplified without any improvement in clarity.
i just can't believe how people like everything they buy. this thing incorporates one of the worse treble productions i've seen to date. do your ears a favor and keep out from this.
after tried some models from this company, i instantly get it. this company just shows you an attractive casing and puts crippled drivers in it to make your money go away. there's a lot better products, don't be fooled by the image.
note: don't worry i've used the original product. mine was bought from accessoryjack, it came with the box. i sold it to an audio-technica fan who used multiple ckm500's and other ath products from different sellers including cdjapan (and he verified it). i also tried the cks55x with another audio-technica fan who already got everything they offer.
I own variety of more expensive IEM however these have to be my favorite. This is mostly due to the huge sound stage which sounds like a full size over the ear headphone.
The highs are crisp clean with good detail and without sibilance.
The mids although slightly recessed still have good presence. The vocals on a good recording will float just above the instruments.
The base is rich and full and will go very low without a lot of bloating. The base may not be big enough to satisfy a base head, however and analytical listen would consider it big. I listen to rock which I would consider the amount just right.
Comparing these to the HA-FXT90 I would say they are pretty close in signature but not the same.
The CKM500 having the edge as they have slightly less treble extension but not a lot. Its just enough to keep it from being strident as the FX90 can sometimes be on certain recordings.