Mm..so I take it that the i4 has the same sound signature as the iSine 20 but done much better? Does it really take after its big brother, the LCD 4?
What gear did you use to listen to the i4? Mojo only? Others? DAPs? Tube amps?
Honestly I haven't listened to the iSINE 20 much since receiving the LCD-i4 prototype before CanJam SoCal. Going from memory, the LCD-i4 is closer to the LCD-4 than it is the iSINE 20. The iSINE 20 has an unexpectedly large soundstage for an IEM, but because the technology is completely different inside the LCD-i4 is in a completely different league. For example, soundstage and instrument placement is better on some tracks with the LCD-i4 than they are on my Ether FLOW. Once I'm back in the office next week I'll spend some time with the LCD-4 and iSINE 20 again and do some quick comparisons.
I listen to it primarily from a Chord Mojo or Sony TA-ZH1ES. I don't own any tube amps and my current DAP doesn't do the LCD-i4 justice.