The JVC FX3X doesn't seem to have much information available as of yet, so when I saw a local store carrying them I decided to pick them up and post some impressions and a review.
I was bored waiting for some gear to arrive so decided to take one for the team (sort of since I can return these for a full refund).
Lets get some basic 's out of the way. These have an aluminum body with a 10mm carbon diaphragm neodymium driver and some form of bass port on the top of the IEM (but this port does not seem to affect isolation as these isolate very well). The design is pretty well done and these are comfortable and can be worn over ear or straight down. The cable is actually nice with a good rubbery feel and weight (but not to much weight), worn over ear the microphonics were very low. It does not have a chin slider though which I don't like and I prefer an L jack versus the straight jack it comes with. It has OK stress relief though and feels like it's built like a tank.
Initial sound is these are what they claim, they are BASS MONSTERS! But they are not quite as one note as that, the mids are fairly clear and present as is the treble. The treble actually is much less offensive to my ears than the FXT90 was. I am not sure I will like the overall sound enough to keep these but so far I am impressed enough that I will continue to burn them in and test them until next week before I make a final decision.
If the bass settles down and the mids and treble improve a bit these may actually become closer to a balanced IEM than they are now but only time will tell this tale. Overal though at $70 I think they may be a good performer at their price range and for those who found the FXT90 to harsh a possible alternative at a better price point.
I would say unless something dramatic happens these will never be a detail monster but they may be a FUN Monster. The sound stage is not huge and the imaging is not super accurate but they are average to slightly above I think.