[Mr_Hym]

Age typically doesn't matter, unless you're talking about headphones from the same family, and even then newer series aren't necessarily better, just different. It all depends on your ears.

 

[Mr_Hym]

Just an update for anyone who may be considering the J4s, after at least 50-60 hours (I stopped counting), the difference is night and day from when I first got them. I've been wearing them over the ear with decored Shure Olive tips, and the bass has really tamed itself, though this may be a negative point to some, as I'm not a huge bass fan. The sibilance has all but disappeared, which helps to let the mids shine a little more. These are now my primary earphones, I'm very happy with them now.
 
UPDATE: So much for durability. The right ear is completely out, it's been less than a month of use. I had just gotten the sound right where I wanted it.

 

[latino886]

Send it in for warranty. Register with the number that came with it, or if you don't have that then you can mail them to JLab and they'll send you a new serial. You can then proceed to replace for free.

 

[RowJoe]

  Just an update for anyone who may be considering the J4s, after at least 50-60 hours (I stopped counting), the difference is night and day from when I first got them. I've been wearing them over the ear with decored Shure Olive tips, and the bass has really tamed itself, though this may be a negative point to some, as I'm not a huge bass fan. The sibilance has all but disappeared, which helps to let the mids shine a little more. These are now my primary earphones, I'm very happy with them now.
 
UPDATE: So much for durability. The right ear is completely out, it's been less than a month of use. I had just gotten the sound right where I wanted it.

I know this is several years old, but I just got the J4Ms for $4.50 a pair, shipped direct from JLab. I don't believe in burn in for IEMs. Coming from car audio, it's pretty laughable. There's no way the driver physically changes that much, if at all. It's all in your head, literally. You just got used to their SQ signature. 

 

[jant71]

Resurrecting a thread that hasn't been posted in for nearly five years to, what, try and start yet another burn in debate?? I don't see Head-fier of the week in your future buddy!