I have been a long time fan of the UE TripleFi 10s..... signature.
I recently purchased the UE900 and what a disappointment..... they took out the fun factor...... less bass and less treble...... and worse of all, very hard to fit properly..... I returned them.
Then I purchase the Sony quad drivers and I really enjoyed the sound signature and comfort, however, without a doubt the Triple Fi were about two steps higher sound quality wise. The Sonys sounded a little congested in comparison while the UEs were fuller + better clarity. I returned them too....
While I was checking the Shure 8400 I checked this thread about FA4.
I wonder how would these ones compare to the UE Triple Fi out of an Ipod Touch 5 + NO eq.